Java full file manipulation instance summary

This example summarizes the Java file operations. Share with you for your reference, as follows:

1. Create folders

//import java.io.*; 
File myFolderPath = new File(%%1); 
try { 
if (!myFolderPath.exists()) { 
myFolderPath.mkdir(); 
} 
} 
catch (Exception e) { 
System.out.println(" Error creating new directory "); 
e.printStackTrace(); 
}

2. Create a file

//import java.io.*; 
File myFilePath = new File(%%1); 
try { 
if (!myFilePath.exists()) { 
myFilePath.createNewFile(); 
} 
FileWriter resultFile = new FileWriter(myFilePath); 
PrintWriter myFile = new PrintWriter(resultFile); 
myFile.println(%%2); 
resultFile.close(); 
} 
catch (Exception e) { 
System.out.println(" Error creating new file "); 
e.printStackTrace(); 
}

Delete files

//import java.io.*; 
File myDelFile = new File(%%1); 
try { 
myDelFile.delete(); 
} 
catch (Exception e) { 
System.out.println(" Error deleting file "); 
e.printStackTrace(); 
}

4. Delete folders

//import java.io.*; 
File delFolderPath = new File(%%1); 
try { 
delFolderPath.delete(); //Delete an empty folder
} 
catch (Exception e) { 
System.out.println(" Error deleting folder "); 
e.printStackTrace(); 
}

Delete all folders under one file

//import java.io.*; 
File delfile=new File(%%1); 
File[] files=delfile.listFiles(); 
for(int i=0;i<files.length;i++){ 
if(files[i].isDirectory()){ 
files[i].delete(); 
} 
}

6. Empty the folder

//import java.io.*; 
File delfilefolder=new File(%%1); 
try { 
if (!delfilefolder.exists()) { 
delfilefolder.delete(); 
} 
delfilefolder.mkdir(); 
} 
catch (Exception e) { 
System.out.println(" An error occurred in the empty directory operation "); 
e.printStackTrace(); 
}

7. Read files

//import java.io.*; 
//Read the data line by line
FileReader fr = new FileReader(%%1); 
BufferedReader br = new BufferedReader(fr); 
String %%2 = br.readLine(); 
while (%%2 != null) { 
%%3 
%%2 = br.readLine(); 
} 
br.close(); 
fr.close();

8. Write to a file

//import java.io.*; 
//Writes data to a file
try { 
FileWriter fw = new FileWriter(%%1); 
fw.write(%%2); 
fw.flush(); 
fw.close(); 
} catch (IOException e) { 
e.printStackTrace(); 
}

9. Write to a random file

//import java.io.*; 
try { 
RandomAcessFile logFile=new RandomAcessFile(%%1,"rw"); 
long lg=logFile.length(); 
logFile.seek(%%2); 
logFile.writeByte(%%3); 
}catch(IOException ioe){ 
System.out.println(" Unable to write to file: "+ioe.getMessage()); 
}

10. Read file properties

//import java.io.*; 
//Access to file properties
File af = new File(%%1); 
if (af.exists()) { 
System.out.println(f.getName() + " Are as follows:   The file length is: " + f.length()); 
System.out.println(f.isFile() ? " Is the file " : " Is not a file "); 
System.out.println(f.isDirectory() ? " Is a directory " : " Not a directory "); 
System.out.println(f.canRead() ? " Can be read " : " Don't "); 
System.out.println(f.canWrite() ? " It's a hidden file " : ""); 
System.out.println(" The last modified date of the folder was: " + new Date(f.lastModified())); 
} else { 
System.out.println(f.getName() + " Are as follows: "); 
System.out.println(f.isFile() ? " Is the file " : " Is not a file "); 
System.out.println(f.isDirectory() ? " Is a directory " : " Not a directory "); 
System.out.println(f.canRead() ? " Can be read " : " Don't "); 
System.out.println(f.canWrite() ? " It's a hidden file " : ""); 
System.out.println(" The document was last modified on: " + new Date(f.lastModified())); 
} 
if(f.canRead()){ 
%%2 
} 
if(f.canWrite()){ 
%%3 
}

11. Write properties

//import java.io.*; 
File filereadonly=new File(%%1); 
try { 
boolean b=filereadonly.setReadOnly(); 
} 
catch (Exception e) { 
System.out.println(" Deny write access: "+e.printStackTrace()); 
}

Enumerate all files in a folder

//import java.io.*; 
//import java.util.*; 
LinkedList<String> folderList = new LinkedList<String>(); 
folderList.add(%%1); 
while (folderList.size() > 0) { 
File file = new File(folderList.peek()); 
folderList.removeLast(); 
File[] files = file.listFiles(); 
ArrayList<File> fileList = new ArrayList<File>(); 
for (int i = 0; i < files.length; i++) { 
if (files[i].isDirectory()) { 
folderList.add(files[i].getPath()); 
} else { 
fileList.add(files[i]); 
} 
} 
for (File f : fileList) { 
%%2=f.getAbsoluteFile(); 
%%3 
} 
}

Copy folders

//import java.io.*; 
//import java.util.*; 
LinkedList<String> folderList = new LinkedList<String>(); 
folderList.add(%%1); 
LinkedList<String> folderList2 = new LinkedList<String>(); 
folderList2.add(%%2+ %%1.substring(%%1.lastIndexOf("//"))); 
while (folderList.size() > 0) { 
(new File(folderList2.peek())).mkdirs(); //Create a new folder if the folder does not exist
File folders = new File(folderList.peek()); 
String[] file = folders.list(); 
File temp = null; 
try { 
for (int i = 0; i < file.length; i++) { 
if (folderList.peek().endsWith(File.separator)) { 
temp = new File(folderList.peek() + File.separator 
+ file[i]); 
} else { 
temp = new File(folderList.peek() + File.separator 
+ file[i]); 
} 
if (temp.isFile()) { 
FileInputStream input = new FileInputStream(temp); 
FileOutputStream output = new FileOutputStream( 
folderList2.peek() + File.separator 
+ (temp.getName()).toString()); 
byte[] b = new byte[5120]; 
int len; 
while ((len = input.read(b)) != -1) { 
output.write(b, 0, len); 
} 
output.flush(); 
output.close(); 
input.close(); 
} 
if (temp.isDirectory()) {//If it's a subfolder
for (File f : temp.listFiles()) { 
if (f.isDirectory()) { 
folderList.add(f.getPath()); 
folderList2.add(folderList2.peek() 
+ File.separator + f.getName());
} 
} 
} 
} 
} catch (Exception e) { 
//System.out.println(" error copying entire folder contents ");
e.printStackTrace(); 
} 
folderList.removeFirst(); 
folderList2.removeFirst(); 
}

14. Copy all the folders under one folder to another folder

//import java.io.*; 
//import java.util.*; 
File copyfolders=new File(%%1); 
File[] copyfoldersList=copyfolders.listFiles(); 
for(int k=0;k<copyfoldersList.length;k++){ 
if(copyfoldersList[k].isDirectory()){ 
ArrayList<String>folderList=new ArrayList<String>(); 
folderList.add(copyfoldersList[k].getPath()); 
ArrayList<String>folderList2=new ArrayList<String>(); 
folderList2.add(%%2+"/"+copyfoldersList[k].getName()); 
for(int j=0;j<folderList.length;j++){ 
(new File(folderList2.get(j))).mkdirs(); //Create a new folder if the folder does not exist
File folders=new File(folderList.get(j)); 
String[] file=folders.list(); 
File temp=null; 
try { 
for (int i = 0; i < file.length; i++) { 
if(folderList.get(j).endsWith(File.separator)){ 
temp=new File(folderList.get(j)+"/"+file[i]); 
} 
else{ 
temp=new File(folderList.get(j)+"/"+File.separator+file[i]); 
} 
FileInputStream input = new FileInputStream(temp); 
if(temp.isFile()){ 
FileInputStream input = new FileInputStream(temp); 
FileOutputStream output = new FileOutputStream(folderList2.get(j) + "/" + 
(temp.getName()).toString()); 
byte[] b = new byte[5120]; 
int len; 
while ( (len = input.read(b)) != -1) { 
output.write(b, 0, len); 
} 
output.flush(); 
output.close(); 
input.close(); 
} 
if(temp.isDirectory()){//If it's a subfolder
folderList.add(folderList.get(j)+"/"+file[i]); 
folderList2.add(folderList2.get(j)+"/"+file[i]); 
} 
} 
} 
catch (Exception e) { 
System.out.println(" Error copying entire folder contents "); 
e.printStackTrace(); 
} 
} 
} 
}

15. Move folders

//import java.io.*; 
//import java.util.*; 
LinkedList<String> folderList = new LinkedList<String>(); 
folderList.add(%%1); 
LinkedList<String> folderList2 = new LinkedList<String>(); 
folderList2.add(%%2 + %%1.substring(%%1.lastIndexOf("//"))); 
while (folderList.size() > 0) { 
(new File(folderList2.peek())).mkdirs(); //Create a new folder if the folder does not exist
File folders = new File(folderList.peek()); 
String[] file = folders.list(); 
File temp = null; 
try { 
for (int i = 0; i < file.length; i++) { 
if (folderList.peek().endsWith(File.separator)) { 
temp = new File(folderList.peek() + File.separator 
+ file[i]); 
} else { 
temp = new File(folderList.peek() + File.separator 
+ file[i]); 
} 
if (temp.isFile()) { 
FileInputStream input = new FileInputStream(temp); 
FileOutputStream output = new FileOutputStream( 
folderList2.peek() + File.separator 
+ (temp.getName()).toString()); 
byte[] b = new byte[5120]; 
int len; 
while ((len = input.read(b)) != -1) { 
output.write(b, 0, len); 
} 
output.flush(); 
output.close(); 
input.close(); 
if (!temp.delete()) 
System.out.println(" Error deleting a single file !"); 
} 
if (temp.isDirectory()) {//If it's a subfolder
for (File f : temp.listFiles()) { 
if (f.isDirectory()) { 
folderList.add(f.getPath()); 
folderList2.add(folderList2.peek() 
+ File.separator + f.getName()); 
} 
} 
} 
} 
} catch (Exception e) { 
//System.out.println(" error copying entire folder contents ");
e.printStackTrace(); 
} 
folderList.removeFirst(); 
folderList2.removeFirst(); 
} 
File f = new File(%%1); 
if (!f.delete()) { 
for (File file : f.listFiles()) { 
if (file.list().length == 0) { 
System.out.println(file.getPath()); 
file.delete(); 
} 
} 
}

16. Move all folders under one folder to another directory

//import java.io.*; 
//import java.util.*; 
File movefolders=new File(%%1); 
File[] movefoldersList=movefolders.listFiles(); 
for(int k=0;k<movefoldersList.length;k++){ 
if(movefoldersList[k].isDirectory()){ 
ArrayList<String>folderList=new ArrayList<String>(); 
folderList.add(movefoldersList[k].getPath()); 
ArrayList<String>folderList2=new ArrayList<String>(); 
folderList2.add(%%2+"/"+movefoldersList[k].getName()); 
for(int j=0;j<folderList.length;j++){ 
(new File(folderList2.get(j))).mkdirs(); //Create a new folder if the folder does not exist
File folders=new File(folderList.get(j)); 
String[] file=folders.list(); 
File temp=null; 
try { 
for (int i = 0; i < file.length; i++) { 
if(folderList.get(j).endsWith(File.separator)){ 
temp=new File(folderList.get(j)+"/"+file[i]); 
} 
else{ 
temp=new File(folderList.get(j)+"/"+File.separator+file[i]); 
} 
FileInputStream input = new FileInputStream(temp); 
if(temp.isFile()){ 
FileInputStream input = new FileInputStream(temp); 
FileOutputStream output = new FileOutputStream(folderList2.get(j) + "/" + 
(temp.getName()).toString()); 
byte[] b = new byte[5120]; 
int len; 
while ( (len = input.read(b)) != -1) { 
output.write(b, 0, len); 
} 
output.flush(); 
output.close(); 
input.close(); 
temp.delete(); 
} 
if(temp.isDirectory()){//If it's a subfolder
folderList.add(folderList.get(j)+"/"+file[i]); 
folderList2.add(folderList2.get(j)+"/"+file[i]); 
} 
} 
} 
catch (Exception e) { 
System.out.println(" Error copying entire folder contents "); 
e.printStackTrace(); 
} 
} 
movefoldersList[k].delete(); 
} 
}

Create folders and empty files in another directory as one folder's framework

//import java.io.*; 
//import java.util.*; 
boolean b=false;//An empty file is not created
ArrayList<String>folderList=new ArrayList<String>(); 
folderList.add(%%1); 
ArrayList<String>folderList2=new ArrayList<String>(); 
folderList2.add(%%2); 
for(int j=0;j<folderList.length;j++){ 
(new File(folderList2.get(j))).mkdirs(); //Create a new folder if the folder does not exist
File folders=new File(folderList.get(j)); 
String[] file=folders.list(); 
File temp=null; 
try { 
for (int i = 0; i < file.length; i++) {
if(folderList.get(j).endsWith(File.separator)){ 
temp=new File(folderList.get(j)+"/"+file[i]); 
} 
else{ 
temp=new File(folderList.get(j)+"/"+File.separator+file[i]); 
} 
FileInputStream input = new FileInputStream(temp); 
if(temp.isFile()){ 
if (b) temp.createNewFile(); 
} 
if(temp.isDirectory()){//If it's a subfolder
folderList.add(folderList.get(j)+"/"+file[i]); 
folderList2.add(folderList2.get(j)+"/"+file[i]); 
} 
} 
} 
catch (Exception e) { 
System.out.println(" Error copying entire folder contents "); 
e.printStackTrace(); 
} 
}

Copy files

//import java.io.*; 
int bytesum = 0; 
int byteread = 0; 
File oldfile = new File(%%1); 
try { 
if (oldfile.exists()) { //File existence
FileInputStream inStream = new FileInputStream(oldfile); //Read in the original file
FileOutputStream fs = new FileOutputStream(new File(%%2,oldfile.getName())); 
byte[] buffer = new byte[5120]; 
int length; 
while ( (byteread = inStream.read(buffer)) != -1) { 
bytesum += byteread; //Number of bytes file size
System.out.println(bytesum); 
fs.write(buffer, 0, byteread); 
} 
inStream.close(); 
} 
} 
catch (Exception e) { 
System.out.println(" There was an error copying a single file "); 
e.printStackTrace(); 
}

Copy all the files in one folder to another directory

//import java.io.*; 
File copyfiles=new File(%%1); 
File[] files=copyfiles.listFiles(); 
for(int i=0;i<files.length;i++){ 
if(!files[i].isDirectory()){ 
int bytesum = 0; 
int byteread = 0; 
try { 
InputStream inStream = new FileInputStream(files[i]); //Read in the original file
FileOutputStream fs = new FileOutputStream(new File(%%2,files[i].getName()); 
byte[] buffer = new byte[5120]; 
int length; 
while ( (byteread = inStream.read(buffer)) != -1) { 
bytesum += byteread; //Number of bytes file size
System.out.println(bytesum); 
fs.write(buffer, 0, byteread); 
} 
inStream.close(); 
} catch (Exception e) { 
System.out.println(" There was an error copying a single file "); 
e.printStackTrace(); 
} 
} 
}

20. Extract the extension

String %%2=%%1.substring(%%1.lastIndexOf(".")+1);

21. Extract file names

String %%2=%%1.substring(%%1.lastIndexOf("//")+1);

22. Extract the file path

String %%2=%%1.substring(0,%%1.lastIndexOf("//"));

23. Replace extensions

//import java.io.*; 
File replaceExt=new File(%%1); 
replaceExt.renameTo(replaceExt.getName().split(".")[0]+"."+%%2);

24. Append path

final String path=%%1.endsWith("//")?%%1:%%1+"//"; 
%%3=path+%%2;

25. Move files

//import java.io.*; 
int bytesum = 0; 
int byteread = 0; 
File oldfile = new File(%%1); 
try { 
if (oldfile.exists()) { //File existence
InputStream inStream = new FileInputStream(oldfile); //Read in the original file
FileOutputStream fs = new FileOutputStream(new File(%%2,oldfile.getName())); 
byte[] buffer = new byte[5120]; 
int length; 
while ( (byteread = inStream.read(buffer)) != -1) { 
bytesum += byteread; //Number of bytes file size
//System.out.println(bytesum); 
fs.write(buffer, 0, byteread); 
} 
inStream.close(); 
oldfile.delete(); 
} 
} 
catch (Exception e) { 
System.out.println(" There was an error copying a single file "); 
e.printStackTrace(); 
}

Move all files under one folder to another directory

//import java.io.*; 
File movefile=new File(%%1); 
File[] movefiles=movefile.listFiles(); 
for(int i=0;i<movefiles.length;i++){ 
if(movefiles[i].isFile()){ 
int bytesum = 0; 
int byteread = 0; 
File oldfile = new File(movefiles[i]); 
try { 
if (oldfile.exists()) { //File existence
InputStream inStream = new FileInputStream(oldfile); //Read in the original file
FileOutputStream fs = new FileOutputStream(new File(%%2,oldfile.getName())); 
byte[] buffer = new byte[5120]; 
int length; 
while ( (byteread = inStream.read(buffer)) != -1) { 
bytesum += byteread; //Number of bytes file size
//System.out.println(bytesum); 
fs.write(buffer, 0, byteread); 
} 
inStream.close(); 
oldfile.delete(); 
} 
} 
catch (Exception e) { 
System.out.println(" There was an error copying a single file "); 
e.printStackTrace(); 
} 
} 
}

27. Search for files in specified directory

//import java.io.*; 
String filter="*.*"; 
String path=%%1; 
File file = new File(path); 
if(file.exists()) { 
if(file.isDirectory()) { 
File[] fileArray = file.listFiles(); 
for(File f:fileArray) { 
if(f.isDirectory()) { 
doSearch(filter,f.getPath()); 
} else { 
if(f.getName().indexOf(filter) >= 0) { 
countFiles++; 
result.append(f.getPath() + "/r/n"); 
} 
} 
statusShow1.setText(f.getPath()); 
} 
statusShow2.setText("The numbers of files had been found:" + countFiles); 
} else { 
System.out.println("Couldn't open the path!"); 
} 
} else { 
System.out.println("The path had been apointed was not Exist!"); 
}

28. Open the dialog box

//import java.io.*; 
//import javax.swing.*; 
JFileChooser Jfc = new JFileChooser(); //Create select file dialog box Jfc
if (Jfc.isFileSelectionEnabled()) { 
File %%1 = Jfc.getSelectedFile(); 
}

29. File splitting

//import java.io.* 
try { 
File f=new File(%%1); 
FileInputStream fileInputStream = new FileInputStream(f); 
byte[] buffer = new byte[fileInputStream.available()]; 
FileInputStream.read(buffer); 
fileInputStream.close(); 
String strFileName = f.getName(); 
FileOutputStream fileOutputStream = new FileOutputStream(new File(%%2+"//"+ strFileName + "1")); 
fileOutputStream.write(buffer,0,buffer.length/2); 
fileOutputStream.close(); 
fileOutputStream = new FileOutputStream(new File(%%2+"//"+ strFileName + "2")); 
fileOutputStream.write(buffer, buffer.length/2, buffer.length-buffer.length/2); 
fileOutputStream.close(); 
} catch (ArrayIndexOutOfBoundsException e) { 
System.out.print("using FileStreamDemo src des"); 
e.printStackTrace(); 
} 
catch(IOException e){ 
e.printStackTrace(); 
}

30. File consolidation

//import java.io.* 
String strFileName = %%1.substring(%%1.LastIndexOf("//") + 1); 
try { 
FileInputStream fileInputStream1 = new FileInputStream(new File(%%2 + strFileName + "1")); 
FileInputStream fileInputStream2 = new FileInputStream(new File(%%2 + strFileName + "2")); 
byte[] buffer = new byte[fileInputStream1.available()+fileInputStream2.available()]; 
FileInputStream.read(buffer, 0, fileInputStream1.available()); 
FileInputStream2.read(buffer, fileInputStream1.available(), fileInputStream2.available()); 
fileInputStream.close(); 
fileInputStream2.close(); 
FileOutputStream fileOutputStream = new FileOutputStream(new File(%%2+"//"+ strFileName)); 
fileOutputStream.write(buffer,0,buffer.length); 
fileOutputStream.close(); 
catch(IOException e){ 
e.printStackTrace(); 
}

31. Simple file encryption

//import java.io.* 
try { 
File f=new File((new File(%%1)).getPath()+"//enc_"+(new File(%%1)).getName().split("//")[1]); 
String strFileName = f.getName(); 
FileInputStream fileInputStream = new FileInputStream(%%2+"//"+strFilename); 
byte[] buffer = new byte[fileInputStream.available()]; 
FileInputStream.read(buffer); 
fileInputStream.close(); 
for(int i=0;i<buffer.length;i++) 
{ 
int ibt=buffer[i]; 
ibt+=100; 
ibt%=256; 
buffer[i]=(byte)ibt; 
} 
FileOutputStream fileOutputStream = new FileOutputStream(f); 
fileOutputStream.write(buffer,0,buffer.length); 
fileOutputStream.close(); 
} 
catch(ArrayIndexOutOfBoundException e){ 
e.printStackTrace(); 
} 
catch(IOException e){ 
e.printStackTrace(); 
}

32. File is simply decrypted

//import java.io.* 
try { 
File f=new File(%%1); 
String strFileName = f.getName(); 
FileInputStream fileInputStream = new FileInputStream(%%2+"//enc_"+strFilename); 
byte[] buffer = new byte[fileInputStream.available()]; 
FileInputStream.read(buffer); 
fileInputStream.close(); 
for(int i=0;i<buffer.length;i++) 
{ 
int ibt=buffer[i]; 
ibt-=100; 
ibt+=256; 
ibt%=256; 
buffer[i]=(byte)ibt; 
} 
FileOutputStream fileOutputStream = new FileOutputStream(f); 
fileOutputStream.write(buffer,0,buffer.length); 
fileOutputStream.close(); 
} 
catch(ArrayIndexOutOfBoundException e){ 
e.printStackTrace(); 
} 
catch(IOException e){ 
e.printStackTrace(); 
}

33. Write ini file properties

//import java.io.*; 
//import java.util.*; 
//import java.util.regex.*; 
if (configMap == null) { 
String WriteBuffer = ""; 
configMap = new HashMap<String, Serializable>(); 
String strLine = null; 
String currentNode = null; 
String previousNode = null; 
Vector<Properties> vec = new Vector<Properties>(); 
int row = 0; 
FileReader fileReader = null; 
try { 
fileReader = new FileReader("Config.ini"); 
} catch (FileNotFoundException e1) { 
e1.printStackTrace(); 
} 
BufferedReader bufferedReader = new BufferedReader(fileReader); 
try { 
while ((strLine = bufferedReader.readLine()) != null) { 
String oneLine = strLine.trim(); 
if (oneLine.length() >= 1) { 
Pattern p = Pattern.compile("//[//s*.*//s*//]"); 
int nodelen = oneLine.split("[;]").length;
String[] strArray1 = new String[4]; 
if (nodelen == 1) { 
oneLine = oneLine.split("[;]")[0].trim(); 
} else if (nodelen == 2) { 
strArray1[3] = oneLine.split("[;]")[1].trim(); 
oneLine = oneLine.split("[;]")[0].trim(); 
} 
Matcher m = p.matcher(oneLine); 
if (m.matches()) { 
strArray1[0] = "@Node"; 
strArray1[1] = oneLine; 
strArray1[2] = ""; 
} else { 
int keylen = oneLine.split("=").length; 
if (keylen == 1) { 
strArray1[0] = "@Key"; 
strArray1[1] = oneLine.split("=")[0]; 
strArray1[2] = ""; 
} else if (keylen == 2) { 
strArray1[0] = "@Key"; 
strArray1[1] = oneLine.split("=")[0]; 
strArray1[2] = oneLine.split("=")[1]; 
} else { 
strArray1[0] = "@ElementError"; 
strArray1[1] = ""; 
strArray1[2] = ""; 
strArray1[3] = ""; 
} 
} 
if (strArray1[0].equals("@Node")) { 
previousNode = currentNode; 
currentNode = strArray1[1]; 
if (row > 0) { 
configMap.put(previousNode, vec.elementAt(0)); 
vec.clear(); 
row = 0; 
} 
WriteBuffer += (oneLine + "/r/n"); 
} else if (strArray1[0].equals("@Key") && row == 0) { 
Properties ht = new Properties(); 
ht.setProperty(strArray1[1], strArray1[2]); 
if (strArray1[1].equals(%%1)) { 
WriteBuffer += (%%1+"=" + %%2 + "/r/n"); 
} else 
WriteBuffer += (oneLine + "/r/n"); 
vec.add(0, ht); 
row++; 
} else if (strArray1[0].equals("@Key") && row > 0) { 
Properties ht2 = new Properties(); 
ht2.put(strArray1[1], strArray1[2]); 
vec.clear(); 
vec.add(0, ht2); 
WriteBuffer += (oneLine + "/r/n"); 
row++; 
} 
} 
} 
configMap.put(currentNode, vec.elementAt(0)); 
} catch (FileNotFoundException e) { 
configMap = null; 
e.printStackTrace(); 
} catch (IOException e) { 
configMap = null; 
e.printStackTrace(); 
} finally { 
vec.clear(); 
try { 
bufferedReader.close(); 
fileReader.close(); 
} catch (IOException e) { 
e.printStackTrace(); 
} 
try { 
FileWriter fw = new FileWriter("Config.ini"); 
fw.write(WriteBuffer); 
fw.flush(); 
fw.close(); 
} catch (IOException e) { 
e.printStackTrace(); 
} 
} 
}

34. Read ini file properties

//import java.io.*; 
//import java.util.*; 
//import java.util.regex.*; 
//private HashMap configMap=null; 
private Map<String, Serializable> configMap=null; 
String %%2=null; 
if (configMap == null) { 
configMap = new HashMap<String, Serializable>(); 
String strLine = null; 
String currentNode = null; 
String previousNode = null; 
Vector<Properties> vec = new Vector<Properties>(); 
int row = 0; 
FileReader fileReader = null; 
try { 
fileReader = new FileReader("Config.ini"); 
} catch (FileNotFoundException e1) { 
e1.printStackTrace(); 
} 
BufferedReader bufferedReader = new BufferedReader(fileReader); 
try { 
while ((strLine = bufferedReader.readLine()) != null) { 
String oneLine = strLine.trim(); 
if (oneLine.length() >= 1) { 
Pattern p = Pattern.compile("//[//s*.*//s*//]"); 
int nodelen = oneLine.split("[;]").length; 
String[] strArray1 = new String[4]; 
if (nodelen == 1) { 
oneLine = oneLine.split("[;]")[0].trim(); 
} else if (nodelen == 2) { 
strArray1[3] = oneLine.split("[;]")[1].trim(); 
oneLine = oneLine.split("[;]")[0].trim(); 
} 
Matcher m = p.matcher(oneLine); 
if (m.matches()) { 
strArray1[0] = "@Node"; 
strArray1[1] = oneLine; 
strArray1[2] = ""; 
} else { 
int keylen = oneLine.split("=").length; 
if (keylen == 1) { 
strArray1[0] = "@Key"; 
strArray1[1] = oneLine.split("=")[0]; 
strArray1[2] = ""; 
} else if (keylen == 2) { 
strArray1[0] = "@Key"; 
strArray1[1] = oneLine.split("=")[0]; 
strArray1[2] = oneLine.split("=")[1]; 
} else { 
strArray1[0] = "@ElementError"; 
strArray1[1] = ""; 
strArray1[2] = ""; 
strArray1[3] = ""; 
} 
} 
if (strArray1[0].equals("@Node")) { 
previousNode = currentNode; 
currentNode = strArray1[1]; 
if (row > 0) { 
configMap.put(previousNode, vec.elementAt(0)); 
vec.clear(); 
row = 0; 
} 
} else if (strArray1[0].equals("@Key") && row == 0) { 
Properties ht = new Properties(); 
ht.setProperty(strArray1[1], strArray1[2]); 
if(strArray1[1].equals(%%1)) 
{ 
%%2=strArray1[2]; 
return; 
} 
vec.add(0, ht); 
row++; 
} else if (strArray1[0].equals("@Key") && row > 0) { 
Properties ht2 = new Properties(); 
ht2.put(strArray1[1], strArray1[2]); 
vec.clear(); 
vec.add(0, ht2); 
row++; 
} 
} 
} 
configMap.put(currentNode, vec.elementAt(0)); 
} catch (FileNotFoundException e) { 
configMap = null; 
e.printStackTrace(); 
} catch (IOException e) { 
configMap = null; 
e.printStackTrace(); 
} finally { 
vec.clear(); 
try { 
bufferedReader.close(); 
fileReader.close(); 
} catch (IOException e) { 
e.printStackTrace(); 
} 
} 
}

Merge all files under one file

File combinefiles=new File(%%1); 
File[] files=combinefiles.listFiles(); 
FileOutputStream fs; 
try { 
fs=new FileOutputStream(new File(%%2)); 
} 
catch(IOException e){ 
e.printStackTrace(); 
} 
for(int i=0;i<files.length;i++){ 
if(files[i].isFile()){ 
int bytesum=0; 
int byteread=0; 
try { 
FileInputStream inStream=new FileInputStream(files[i]); 
byte[] buffer = new byte[5120]; 
int length; 
while((byteread=inStream.read(buffer))!=-1){ 
bytesum+=byteread; 
fs.write(buffer,0,byteread); 
} 
inStream.close(); 
} 
catch(Exception e){ 
//Error copying file
e.printStackTrace(); 
} 
} 
} 
try { 
fs.close(); 
} 
catch(IOException e){ 
{ 
e.printStackTrace(); 
}

36. Write ini file properties

//import java.io.*; 
//import java.util.*; 
//import java.util.regex.*; 
//private HashMap configMap=null; 
private Map<String, Serializable> configMap=null; 
if(configMap==null) { 
String strLine=null; 
String currentNode=null; 
String previousNode=null; 
Vector<Properties> vec=new Vector<Properties>(); 
int row=0; 
FileReader fileReader = null; 
try { 
fileReader = new FileReader(%%1); 
} catch (FileNotFoundException e1) { 
e1.printStackTrace(); 
} 
BufferedReader bufferedReader=new BufferedReader(fileReader); 
try { 
while((strLine=bufferedReader.readLine())!=null) { 
String oneLine=strLine.trim(); 
if(oneLine.length()>=1) { 
Pattern p=Pattern.compile("//[//s*.*//s*//]"); 
int nodelen=oneLine.split("[;]").length; 
String[] strArray1=new String[4]; 
if(nodelen==1) { 
oneLine=oneLine.split("[;]")[0].trim(); 
} 
else if(nodelen==2) { 
strArray1[3]=oneLine.split("[;]")[1].trim(); 
oneLine=oneLine.split("[;]")[0].trim(); 
} 
Matcher m=p.matcher(oneLine); 
if(m.matches()) { 
strArray1[0]="@Node"; 
strArray1[1]=oneLine; 
strArray1[2]=""; 
} else { 
int keylen=oneLine.split("=").length; 
if(keylen==1) { 
strArray1[0]="@Key"; 
strArray1[1]=oneLine.split("=")[0]; 
strArray1[2]=""; 
} else if(keylen==2) { 
strArray1[0]="@Key"; 
strArray1[1]=oneLine.split("=")[0]; 
strArray1[2]=oneLine.split("=")[1]; 
} else { 
strArray1[0]="@ElementError"; 
strArray1[1]=""; 
strArray1[2]=""; 
strArray1[3]=""; 
} 
} 
if(strArray1[0].equals("@Node")) { 
previousNode=currentNode; 
currentNode=strArray1[1]; 
if(row>0) { 
configMap.put(previousNode,vec.elementAt(0)); 
//"size:"+configMap.size() 
vec.clear(); 
row=0; 
} 
} else if(strArray1[0].equals("@Key") && row==0) { 
Properties ht=new Properties(); 
ht.setProperty(strArray1[1],strArray1[2]); 
vec.add(0,ht); 
row++; 
} else if(strArray1[0].equals("@Key") && row>0) { 
Properties ht2=new Properties(); 
ht2.put(strArray1[1],strArray1[2]); 
vec.clear(); 
vec.add(0,ht2); 
row++; 
} 
} 
} 
configMap.put(currentNode,vec.elementAt(0)); 
} catch (FileNotFoundException e) { 
configMap=null; 
e.printStackTrace(); 
} catch (IOException e) { 
configMap=null; 
e.printStackTrace(); 
} finally { 
vec.clear(); 
try { 
bufferedReader.close(); 
fileReader.close(); 
} catch (IOException e) { 
e.printStackTrace(); 
} 
} 
} 
String nodeKey="["+%%2+"]"; 
Properties ht=null; 
if(configMap.containsKey(nodeKey)) { 
ht=(Properties)configMap.get(nodeKey); 
} else { 
ht=(Properties)configMap.put(nodeKey,%%3); 
} 
try { 
ht.setProperty(%%3,%%4); 
} catch (NullPointException e) { 
e.printStackTrace(); 
} 
FileWriter fw= null; 
BufferedWriter bw= null; 
try { 
fw = new FileWriter(%%1); 
bw=new BufferedWriter(fw); 
} catch (IOException e) { 
e.printStackTrace(); 
} 
Set keys=configMap.keySet(); 
Iterator ite=keys.iterator(); 
while(ite.hasNext()) { 
String oneKey=(String)ite.next(); 
try { 
bw.write(oneKey+"/n"); 
} catch (IOException e) { 
e.printStackTrace(); 
} 
ht=(Properties)configMap.get(oneKey); 
ht.list(new PrintWriter(bw,true)); 
}

37. Get the current path

String %%1=this.getClass().getResource("/").getPath();

38. Read the XML database

//import java.io.*; 
//import javax.xml.parsers.*; 
//import org.xml.sax.*; 
//import org.w3c.dom.*; 
private Document document; 
File xml_file=new File(%%1); 
DocumentBuilderFactory factory=DocumentBuilderFactory.newInstance(); 
try { 
DocumentBuilder builder=factory.newDocumentBuilder(); 
document=builder.parse(xml_file); 
} catch(Exception e) { 
e.printStackTrace(); 
} 
String subNodeTag=%%2; 
Element rootNode=document.getDocumentElement(); 
//%%2="serverList" //%%4="id" //%%6="port" 
//%%3="server" //%%5="ipaddr" 
NodeList nlist=rootNode.getElementsByTagName(subNodeTag); 
int len=nlist.getLength(); 
Node x=null; 
for(int i=0;i<len;i++) { 
x=nlist.item(i); 
String getNodeAttrValue=null; 
NamedNodeMap attrList=node.getAttributes(); 
for(int j=0;j<attrList.getLength();j++) { 
if(attrList.item(j).getNodeName().compareTo(%%7)==0) { 
getNodeAttrValue=attrList.item(j).getNodeValue(); 
break; 
} 
} 
if(getNodeAttrValue.compareTo(%%8)==0) 
break; 
} 
String %%9=null; 
if(x!=null) { 
NodeList nlist=node.getChildNodes(); 
int len=nlist.getLength(); 
Node currentNode; 
String nodeName; 
for(int i=0;i<len;i++) { 
currentNode=nlist.item(i); 
nodeName=currentNode.getNodeName(); 
if(nodeName.equals(%%5)==0) { 
%%9=document.getElementValue(currentNode); 
break; 
} 
} 
}

39. Write to the XML database

//import java.io.*; 
//import javax.xml.parsers.*; 
//import org.xml.sax.*; 
//import org.w3c.dom.*; 
//import javax.xml.transform.*; 
//import javax.xml.transform.dom.*; 
//import javax.xml.transform.stream.*; 
private Document document; 
private Element node; 
File xml_file=new File(%%1); 
DocumentBuilderFactory factory=DocumentBuilderFactory.newInstance(); 
try { 
DocumentBuilder builder=factory.newDocumentBuilder(); 
document=builder.parse(xml_file); 
} catch(Exception e) { 
e.printStackTrace(); 
} 
String subNodeTag=%%2; 
Element rootNode=document.getDocumentElement(); 
//%%2="serverList" //%%4="id" //%%6="port" 
//%%3="server" //%%5="ipaddr" 
NodeList nlist=rootNode.getElementByTagName(subNodeTag); 
node=document.createElement(%%3); 
node.setAttribute(%%4,nlist.getLength()+1).toString()); 
node.appendChild(document.createTextNode("/n"); 
Element ipNode=document.createElement(%%5); 
ipNode.appendChild(document.createTextNode(%%8)); 
node.appendChild(ipNode); 
node.appendChild(document,createTextNode("/n"); 
Element port=document.createElement(%%6); 
port.appendChild(document.createTextNode(%%9)); 
node.appendChild(port); 
node.appendChild(document,createTextNode("/n"); 
nlist.appendChild(node); 
TransformerFactory tFactory=TransformerFactory.newInstance(); 
Transformer transformer=null; 
try { 
transformer=tFactory.newTransformer(); 
DOMSource source=new DOMSource(document); 
StreamResult result=new StreamResult(xml_file); 
transformer.transform(source,result); 
} catch(Exception e) { 
e.printStackTrace(); 
}

40.ZIP file

//import java.io.*; 
//import java.util.zip.*; 
//Create the file input stream object
FileInputStream fis=new FileInputStream(%%1); 
//Create the file output stream object
FileOutputStream fos=new FileOutputStream(%%2); 
//Create a ZIP data output stream object
ZipOutputStream zipOut=new ZipOutputStream(fos); 
//Creates an entry point to the compressed original file
ZipEntry entry=new ZipEntry(args[0]); 
zipOut.putNextEntry(entry); 
//Output data to a compressed file
int nNumber; 
byte[] buffer=new byte[1024]; 
while((nNumber=fis.read(buffer))!=-1) 
zipOut.write(buffer,0,nNumber); 
//Close the created flow object
zipOut.close(); 
fos.close(); 
fis.close(); 
} 
catch(IOException e) 
{ 
System.out.println(e); 
}

41. Get the full path to the application

String %%1=System.getProperty("user.dir");

42. ZIP decompression

//import java.io.*; 
//import java.util.zip.*; 
try{ 
//Create an instance of the file input stream object
FileInputStream fis=new FileInputStream(%%1); 
//Create a ZIP compressed format input stream object instance
ZipInputStream zipin=new ZipInputStream(fis); 
//Create an instance of the file output stream object
FileOutputStream fos=new FileOutputStream(%%2); 
//Gets an instance of the Entry object
ZipEntry entry=zipin.getNextEntry(); 
byte[] buffer=new byte[1024]; 
int nNumber; 
while((nNumber=zipin.read(buffer,0,buffer.length))!=-1) 
fos.write(buffer,0,nNumber); 
//Close the file stream object
zipin.close(); 
fos.close(); 
fis.close(); 
} 
catch(IOException e) { 
System.out.println(e); 
}

Recursively deletes files from a directory

//import java.io.*; 
//import java.util.*; 
ArrayList<String> folderList = new ArrayList<String>(); 
folderList.add(%%1); 
for (int j = 0; j < folderList.size(); j++) { 
File file = new File(folderList.get(j)); 
File[] files = file.listFiles(); 
ArrayList<File> fileList = new ArrayList<File>(); 
for (int i = 0; i < files.length; i++) { 
if (files[i].isDirectory()) { 
folderList.add(files[i].getPath()); 
} else { 
fileList.add(files[i]); 
} 
} 
for (File f : fileList) { 
f.delete(); 
} 
}

43.ZIP folder

//import java.io.*; 
//import org.apache.tools.zip.ZipOutputStream;
//This package is in ant.jar and should be downloaded from the official website
//import java.util.zip.*; 
try { 
String zipFileName = %%2; //File name after packaging
File f=new File(%%1); 
ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipFileName)); 
String base= ""; 
if (f.isDirectory()) { 
File[] fl = f.listFiles(); 
out.putNextEntry(new org.apache.tools.zip.ZipEntry(base + "/")); 
base = base.length() == 0 ? "" : base + "/"; 
for (int i = 0; i < fl.length; i++) { 
zip(out, fl[i], base + fl[i].getName()); 
} 
}else { 
out.putNextEntry(new org.apache.tools.zip.ZipEntry(base)); 
FileInputStream in = new FileInputStream(f); 
int b; 
while ( (b = in.read()) != -1) { 
out.write(b); 
} 
in.close(); 
} 
out.close(); 
}catch (Exception ex) { 
ex.printStackTrace(); 
}

44. Java authentication DTD

//import java.io.*; 
//import javax.xml.parsers.*; 
//import org.xml.sax.*; 
//import org.w3c.dom.*; 
try { 
InputStream in=new FileInputStream(filePath); 
SAXReader saxReader = new SAXReader(); 
this.document = saxReader.read(in); 
DocumentBuilderFactory factory = null; 
factory = DocumentBuilderFactory.newInstance(); 
//Do DTD checking
factory.setValidating(true); 
} catch (Exception e) { 
}

45. The authentication Schema

//import java.io.*; 
//import javax.xml.parsers.*; 
//import org.xml.sax.*; 
//import org.w3c.dom.*; 
String xsdFileName = /"Q:////_dev_stu////xsdtest////src////note.xsd/"; 
try { 
//Create the default XML error handler
XMLErrorHandler errorHandler = new XMLErrorHandler(); 
//Gets an instance of a sax-based parser
SAXParserFactory factory = SAXParserFactory.newInstance(); 
//The parser validates the XML content as it is parsed.
factory.setValidating(true); 
//Specifying the parser generated from this code will provide support for XML namespaces.
factory.setNamespaceAware(true); 
//Create a new instance of SAXParser using the currently configured factory parameters.
SAXParser parser = factory.newSAXParser(); 
//Create a read tool
SAXReader xmlReader = new SAXReader(); 
//Gets the XML document instance to validate
Document xmlDocument = (Document) xmlReader.read(new File(xmlFileName)); 
//Sets specific properties in the underlying implementation of XMLReader. The list of core functions and properties can be found at http: zhaosax.sourceforge.net/ ? Selected =get-set.
parser.setProperty( 
/"http://java.sun.com/xml/jaxp/properties/schemaLanguage", 
/"http://www.w3.org/2001/XMLSchema"); 
parser.setProperty( 
/"http://java.sun.com/xml/jaxp/properties/schemaSource", 
/"file:/" + xsdFileName); 
//Create a SAXValidator validator and set the properties of the validator
SAXValidator validator = new SAXValidator(parser.getXMLReader()); 
//Set the error handler of the validation tool so that when an error occurs, you can get an error message from the processor object.
validator.setErrorHandler(errorHandler); 
//check
validator.validate(xmlDocument); 
XMLWriter writer = new XMLWriter(OutputFormat.createPrettyPrint()); 
//If the error message is not null, the validation failed and the error message is printed
if (errorHandler.getErrors().hasContent()) { 
System.out.println(/"XML File by XSD File validation failed! /"); 
writer.write(errorHandler.getErrors()); 
} else { 
System.out.println(/"Good! XML File by XSD File validation successful! /"); 
} 
} catch (Exception ex) { 
System.out.println(/"XML file : /" + xmlFileName + /"  through XSD file :/" + xsdFileName + /" Check failed. /n The reason:  /" + ex.getMessage 
()); 
ex.printStackTrace(); 
} 
}

46. Grep

//import java.util.regex.*; 
//import java.io.*; 
/** 
* Simple implementation of the ubiquitous grep command. 
* First argument is the regular expression to search for (remember to 
* quote and/or escape as appropriate). All following arguments are 
* filenames to read and search for the regular expression. 
* 
* Created: April, 2002 
* @author Ron Hitchens (ron@ronsoft.com) 
* @version $Id: SimpleGrep.java,v 1.1 2002/05/07 02:21:08 ron Exp $ 
*/ 
public static void main (String [] argv) 
throws Exception 
{ 
if (argv.length < 2) { //End the program if the argument line has no input arguments
System.out.println ("Usage: regex file [ ... ]"); 
return; 
} 
Pattern pattern = Pattern.compile (argv [0]); //The first argument is the string to match
Matcher matcher = pattern.matcher (""); 
//Read each file at once
for (int i = 1; i < argv.length; i++) { 
String file = argv [i]; //The second argument starts with a filename.
BufferedReader br = null; 
String line; 
try { 
br = new BufferedReader (new FileReader (file)); //Open the file
} catch (IOException e) { 
//An exception occurs if the file is not opened
System.err.println ("Cannot read '" + file 
+ "': " + e.getMessage()); 
continue; 
} 
while ((line = br.readLine()) != null) { //Read in a line until the file ends
matcher.reset (line); //Matching string
if (matcher.find()) { //If there is a matching string, output
System.out.println (file + ": " + line); 
} 
} 
br.close(); //Close the file
} 
}

47. Create multiple levels of directories directly

//import java.io.*; 
File f=new File(%%1); 
f.mkdirs();

48. Batch renaming

//import java.io.*; 
File target = new File("%%1"); 
String[] files = target.list(); 
File f = null; 
String filename = null; 
for (String file : files) { 
f = new File(fl, file); 
filename = f.getName(); 
if (filename.substring(filename.lastIndexOf 
(".")).equalsIgnoreCase( 
"%%2")) { 
f.renameTo(new File(target.getAbsolutePath(), 
filename.replace( 
"%%2", "%%3"))); 
//You can use replace over and over again, or you can use regular expressions
//".txt" ".bat"
} 
}

49. Text search substitution

//import java.nio.*; 
String s1=%%1; 
String s2=%%2; 
String s3=%%3; 
int pos=%%4; 
 
int i,j,k=0; 
i = pos; 
j = 0; 
//Convert s1 to StringBuffer type for operation
repStr = new StringBuffer(s1); 
while(i<repStr.length()&&j<s2.length()) 
{ 
if(repStr.charAt(i) == s2.charAt(j)) 
{ 
++i; ++j; 
if(j==s2.length()) 
{ 
 
k = k+1; 
repStr.replace(i-j,i,s3); 
//Reassign j to start a new comparison
j = 0; 
} 
} 
else {i = i-j+1; j = 0;} 
} 
return k;

50. File association

//import java.io.*; 
try { 
Runtime.getRuntime().exec(%%1); //"assoc .txt =mynote" "assoc [.ext[=[filetype]]]" 
} catch (IOException e) { 
e.printStackTrace(); 
}

52. Set JDK environment variables

@echo off 
IF EXIST %1/bin/java.exe ( 
rem  If entered correctly  Java2SDK  Install the directory and start setting environment variables  
@setx JAVA_HOME %1 
@setx path %path%;%JAVA_HOME%/bin 
@setx classpath %classpath%;. 
@setx classpath %classpath%;%JAVA_HOME%/lib/tools.jar 
@setx classpath %classpath%;%JAVA_HOME%/lib/dt.jar 
@setx classpath %classpath%;%JAVA_HOME%/jre/lib/rt.jar 
@echo on 
@echo Java 2 SDK  Environment parameters are set, exit normally.  
) ELSE ( 
IF "%1"=="" ( 
rem  If no installation directory is provided, exit after prompt  
@echo on 
@echo  Does not provide  Java2SDK  Installation directory , Do not make any Settings, now exit the environment variable Settings.  
) ELSE ( 
rem  If a non-empty installation directory is provided but not available bin/java.exe , the directory specified is the wrong directory  
@echo on 
@echo  illegal  Java2SDK  Installation directory , Do not make any Settings, now exit the environment variable Settings.  
) 
) 
//http://sourceforge.net/projects/jregistrykey/ 
//import ca.beq.util.win32.registry.*; 
//import java.util.*;

1. Open the key

RegistryKey r = new RegistryKey(RootKey.HKEY_LOCAL_MACHINE, 
"SOFTWARE//Microsoft//Windows//CurrentVersion//Explorer//Shell Folders");

2. The add button

RegistryKey r = new RegistryKey(RootKey.HKEY_CURRENT_USER, "Software//BEQ 
Technologies"); 
r.create();

3. Write a string value

RegistryKey r = new RegistryKey(RootKey.HKEY_CURRENT_USER, "Software//BEQ Technologies"); 
RegistryValue v = new RegistryValue("myVal", ValueType.REG_SZ, "data"); 
r.setValue(v); 

4. Get a DWORD value

RegistryKey r = new RegistryKey(RootKey.HKEY_CURRENT_USER, "Software//BEQ Technologies"); 
if(r.hasValue("myValue")) { 
RegistryValue v = r.getValue("myValue"); 
v.setType(ValueType.REG_DWORD); 
} // if

53. Select folder dialog box

 
JFileChooser chooser = new JFileChooser(); 
chooser.setCurrentDirectory(new File(".")); 
chooser.setFileFilter(new javax.swing.filechooser.FileFilter() { 
public boolean accept(File f) { 
return f.getName().toLowerCase().endsWith(".gif") 
|| f.isDirectory(); 
} 
public String getDescription() { 
return "GIF Images"; 
} 
}); 
int r = chooser.showOpenDialog(null); 
if (r == JFileChooser.APPROVE_OPTION) { 
String name = chooser.getSelectedFile().getPath(); 
// label.setIcon(new ImageIcon(name)); 
}

54. Delete an empty folder

//import java.io.*; 
File f=new File(%%1); 
if (isFolerNull(f)) { 
for (File file :f.listFiles()) { 
if (file.list().length == 0) { 
System.out.println(file.getPath()); 
file.delete(); 
} 
} 
}

Send data to clipboard

//import java.awt.*; 
//import java.awt.datatransfer.*; 
Clipboard clipboard = Toolkit.getDefaultToolkit().getSystemClipboard(); 
Transferable tText = new StringSelection(%%1); 
clipboard.setContents(tText, null);

56. Fetch data from clipboard

//import java.awt.*; 
//import java.awt.datatransfer.*; 
//Gets a Java object constructed of transportable data from the system clipboard
Transferable t = Toolkit.getDefaultToolkit() 
.getSystemClipboard().getContents(null); 
try { 
if (t != null 
&& t.isDataFlavorSupported(DataFlavor.stringFlavor)) { 
//Because the original clipboard has a variety of information, such as text, pictures, documents, and so on
//First determine whether the data to be transferred at the beginning is text or not, and if so, get the text
String s = (String) t 
.getTransferData(DataFlavor.stringFlavor); 
//Also, since DataFlavor is of multiple types in the Transferable,
//So pass in the parameter DataFlavor, specifying what type of Data to get.
System.out.println(s); 
} 
} catch (UnsupportedFlavorException ex) { 
ex.printStackTrace(); 
} catch (IOException ex) { 
ex.printStackTrace(); 
}

Gets the parent path of the file path
The same code at the page code block index 2
58. Create shortcuts

//import java.io.*; 
try { 
PrintWriter pw=new PrintWriter(new FileOutputStream("C:/a.bat")); 
pw.println(%%1);"C:/a.txt" 
pw.close(); 
} 
catch(IOException e){ 
e.printStackTrace(); 
}

59. A shortcut menu pops up

//MouseEvent e 
JPopupMenu jpm=new JPopupMenu();
show(jpm,x,y);

60. Folder copy to merge operation

 
JFileChooser Jfc = new JFileChooser(" Select the source path "); //Create a select file dialog
//Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%1 = Jfc.getSelectedFile().getParent(); 
Jfc = new JFileChooser(" Please select the target path "); //  Create a select file dialog Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%2 = Jfc.getSelectedFile().getParent(); 
LinkedList<String> folderList = new LinkedList<String>(); 
folderList.add(%%1); 
LinkedList<String> folderList2 = new LinkedList<String>(); 
folderList2.add(%%2+ %%1.substring(%%1.lastIndexOf("//"))); 
while (folderList.size() > 0) { 
(new File(folderList2.peek())).mkdirs(); //Create a new folder if the folder does not exist
File folders = new File(folderList.peek()); 
String[] file = folders.list(); 
File temp = null; 
try { 
for (int i = 0; i < file.length; i++) { 
if (folderList.peek().endsWith(File.separator)) { 
temp = new File(folderList.peek() + File.separator 
+ file[i]); 
} else { 
temp = new File(folderList.peek() + File.separator 
+ file[i]); 
} 
if (temp.isFile()) { 
FileInputStream input = new FileInputStream(temp); 
FileOutputStream output = new FileOutputStream( 
folderList2.peek() + File.separator 
+ (temp.getName()).toString()); 
byte[] b = new byte[5120]; 
int len; 
while ((len = input.read(b)) != -1) { 
output.write(b, 0, len); 
} 
output.flush(); 
output.close(); 
input.close(); 
} 
if (temp.isDirectory()) {//If it's a subfolder
for (File f : temp.listFiles()) { 
if (f.isDirectory()) { 
folderList.add(f.getPath()); 
folderList2.add(folderList2.peek() 
+ File.separator + f.getName()); 
} 
} 
} 
} 
} catch (Exception e) { 
//System.out.println(" error copying entire folder contents ");
e.printStackTrace(); 
} 
folderList.removeFirst(); 
folderList2.removeFirst(); 
}

61. Folder moved to integration operation

 
JFileChooser Jfc = new JFileChooser(" Select the source path "); //Create a select file dialog
//Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%1 = Jfc.getSelectedFile().getParent(); 
Jfc = new JFileChooser(" Please select the target path "); //  Create a select file dialog Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%2 = Jfc.getSelectedFile().getParent();

62. Copy all folders under directory to merge operation

 
JFileChooser Jfc = new JFileChooser(" Select the source path ");
//Create a select file dialog
//Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%1 = Jfc.getSelectedFile().getParent(); 
Jfc = new JFileChooser(" Please select the target path "); //  Create a select file dialog Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%2 = Jfc.getSelectedFile().getParent();

63. Move all folders under directory to merge operation

 
JFileChooser Jfc = new JFileChooser(" Select the source path ");
//Create a select file dialog
//Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%1 = Jfc.getSelectedFile().getParent(); 
Jfc = new JFileChooser(" Please select the target path ");
//  Create a select file dialog Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%2 = Jfc.getSelectedFile().getParent();

64. Copy all files in the directory to the merge operation

 
JFileChooser Jfc = new JFileChooser(" Select the source path ");
//Create a select file dialog
//Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%1 = Jfc.getSelectedFile().getParent(); 
Jfc = new JFileChooser(" Please select the target path ");
//  Create a select file dialog Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%2 = Jfc.getSelectedFile().getParent();

65. Move all files in the directory to the merge operation

 
JFileChooser Jfc = new JFileChooser(" Select the source path ");
//Create a select file dialog
//Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%1 = Jfc.getSelectedFile().getParent(); 
Jfc = new JFileChooser(" Please select the target path ");
//  Create a select file dialog Square box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%2 = Jfc.getSelectedFile().getParent();

Unzip the target zip file to the specified folder

67. Create a directory copy consolidation operation

 
JFileChooser Jfc = new JFileChooser(" Select the source path ");
//Create a select file dialog
 Square box  Jfc 
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%1 = Jfc.getSelectedFile().getParent(); 
Jfc = new JFileChooser(" Please select the target path ");
//Create select file dialog box Jfc
if (!Jfc.isFileSelectionEnabled()) { 
return; 
} 
String %%2 = Jfc.getSelectedFile().getParent();

68. Open a web page

//import java.io.*; 
try{ 
String command = "C://Program Files//Internet Explorer//Iexplore.exe "+%%1; 
Runtime.getRuntime().exec(command); 
} catch (IOException ex) { 
ex.printStackTrace(); 
}

69. Delete the empty folder consolidation operation

70. After getting all the partitions of the disk, remove the cd-rom character (replace it with "/0") and place the result in the array allfenqu[], in which each
Each element represents a partition character, not including :// such a path, allfenqu[] array at the beginning of the storage is all the characters.  
When I test the correct result with this code, the cd-rom character is removed:

String root; //Root represents the path of the character
for(i=0;i<20;i++) //0-20 represents the largest number of dials
{ 
root.Format("%c://",allfenqu[i]); 
if(GetDriveType(root)==5) 
allfenqu[i]='/0'; 
} 
 But I couldn't get rid of the cd-rom character when I used this code, allfenqu[] Will still contain the cd-rom character:  
String root; 
for(i=0;i<20;i++) 
{ 
root=allfenqu[i]+"://"; 
if(GetDriveType(root)==5) 
allfenqu[i]='/0'; 
}

Activate a program or program associated file

//import java.io.*; 
try { 
Runtime.getRuntime().exec(%%1); 
} catch (IOException e) { 
e.printStackTrace(); 
}

72. The HTTP download

public class DownloadCSVFileAction extends Action{ 
public ActionForward execute(ActionMapping mapping, ActionForm form, 
HttpServletRequest request, HttpServletResponse response) throws Exception { 
try { 
String fileName = request.getParameter( "fileName "); 
long maID = Long.parseLong(request.getParameter( "maID ")); 
String filePath = request.getSession().getServletContext 
().getRealPath( "/ ")+ "csv/ "+maID+ "/ "+fileName; 
File fdown = new File(filePath); 
int filelength = Integer.parseInt(String.valueOf 
(fdown.length())); 
//The download type
response.setContentType( "application/text;charset=GB2312 "); 
response.setHeader( "Content-Dispositon ", "attachment;filename= 
 Sales details .csv "); //CSV is the file name of the download file I want, but the download dialog box shows
 Below is the  downLoadCSVFile.do 
response.setContentLength(filelength); 
byte b[]=new byte[filelength]; 
FileInputStream fi=new FileInputStream(fdown); 
OutputStream o=response.getOutputStream(); 
int n = 0; 
while((n=fi.read(b))!=-1) { 
o.write(b,0,n); 
} 
fi.close(); 
o.close(); 
return null; 
}catch (Exception e) { 
request.setAttribute( "ERROR ", e); 
return mapping.findForward( "error "); 
} 
} 
}

The corresponding download type

private String getContentType(String fileName) { 
String fileNameTmp = fileName.toLowerCase(); 
String ret = ""; 
if (fileNameTmp.endsWith("txt")) { 
ret = "text/plain"; 
} 
if (fileNameTmp.endsWith("gif")) { 
ret = "image/gif"; 
} 
if (fileNameTmp.endsWith("jpg")) { 
ret = "image/jpeg"; 
} 
if (fileNameTmp.endsWith("jpeg")) { 
ret = "image/jpeg"; 
} 
if (fileNameTmp.endsWith("jpe")) { 
ret = "image/jpeg"; 
} 
if (fileNameTmp.endsWith("zip")) { 
ret = "application/zip"; 
} 
if (fileNameTmp.endsWith("rar")) { 
ret = "application/rar"; 
} 
if (fileNameTmp.endsWith("doc")) { 
ret = "application/msword"; 
} 
if (fileNameTmp.endsWith("ppt")) { 
ret = "application/vnd.ms-powerpoint"; 
} 
if (fileNameTmp.endsWith("xls")) { 
ret = "application/vnd.ms-excel"; 
} 
if (fileNameTmp.endsWith("html")) { 
ret = "text/html"; 
} 
if (fileNameTmp.endsWith("htm")) { 
ret = "text/html"; 
} 
if (fileNameTmp.endsWith("tif")) { 
ret = "image/tiff"; 
} 
if (fileNameTmp.endsWith("tiff")) { 
ret = "image/tiff"; 
} 
if (fileNameTmp.endsWith("pdf")) { 
ret = "application/pdf"; 
} 
return ret; 
}

73. The FTP to download

 
//If the file is in a directory, add fc.cd("foodir");
// Like to download ftp://ftp.xx.com/index.html Is:  
try 
{ 
FtpClient fc=new FtpClient("ftp.xx.com"); 
fc.login("username","888888"); 
int ch; 
File fi = new File("c://index.html"); 
RandomAccessFile getFile = new RandomAccessFile(fi,"rw"); 
getFile.seek(0); 
TelnetInputStream fget=fc.get("index.html"); 
DataInputStream puts = new DataInputStream(fget); 
while ((ch = puts.read()) >= 0) { 
getFile.write(ch); 
} 
fget.close(); 
getFile.close(); 
fc.closeServer(); 
} 
catch (IOException ex) 
{ 
ex.printStackTrace(); 
}

74. Write an image to the clipboard setClipboardImage

 
private final Image image; 
Transferable trans = new Transferable() { 
public DataFlavor[] getTransferDataFlavors() { 
return new DataFlavor[] { DataFlavor.imageFlavor }; 
} 
public boolean isDataFlavorSupported(DataFlavor flavor) { 
return DataFlavor.imageFlavor.equals(flavor); 
} 
public Object getTransferData(DataFlavor flavor) 
throws UnsupportedFlavorException, IOException { 
if (isDataFlavorSupported(flavor)) 
return image; 
throw new UnsupportedFlavorException(flavor); 
} 
}; 
Toolkit.getDefaultToolkit().getSystemClipboard().setContents(trans, 
null);

Copy images from clipboard to form

Delete all files under folders without deleting folders under folders

//import java.io.*; 
//import java.util.*; 
LinkedList<String> folderList = new LinkedList<String>(); 
folderList.add(%%1); 
while (folderList.size() > 0) { 
File file = new File(folderList.peek()); 
folderList.removeLast(); 
File[] files = file.listFiles(); 
ArrayList<File> fileList = new ArrayList<File>(); 
for (int i = 0; i < files.length; i++) { 
if (files[i].isDirectory()) { 
folderList.add(files[i].getPath()); 
} else { 
fileList.add(files[i]); 
} 
} 
for (File f : fileList) { 
f.delete(); 
} 
}

I hope this article has been helpful to you in Java programming.