java FileWriter Append File and File Rename Method
- 2021-11-02 00:48:31
- OfStack
FileWriter Append Files and Rename Files
I won't talk too much, let's just look at the code ~
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
public class FileWriterUtil {
/**
* Append files: Use FileWriter
*/
public static void appendMethod(String fileName, String content) {
try {
// Open 1 Writer, the first in the constructor 2 Parameters true Indicates writing a file in appended form
FileWriter writer = new FileWriter(fileName, true);
writer.write(content);
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* Modify file name
* @param oldFilePath
* @param newFileName
*/
public static void reNameLogFile(String oldFilePath,String newFileName){
File f=new File(oldFilePath);
String c=f.getParent();
// File mm=new File(c + File.pathSeparator + newFileName + "_" + CommonUtil.getCurrTimeForString());
File mm=new File(c + "/" + newFileName + "_" + CommonUtil.getBeforeDateStr());
if(f.renameTo(mm)){
System.out.println(" The file name was modified successfully !");
}else{
System.out.println(" Failed to modify file name ");
}
}
public static void main(String[] args) {
String fileName = "/Users/qin/Downloads/callLog.txt";
String content = "new append!";
FileWriterUtil.appendMethod(fileName, content);
FileWriterUtil.appendMethod(fileName, "append end. \n");
FileWriterUtil.reNameLogFile("/Users/qin/Downloads/callLog.txt","rayda");
}
}
Java PrintWriter & FileWriter Write Append to File
Write files with PrintWriter
import java.io.IOException;
import java.io.PrintWriter;
public class PrintWriteDemo
{
public static void main(String[] args) throws IOException
{
PrintWriter out = new PrintWriter("01.txt");
out.print("the quick brown fox");
out.println(" jumps over the lazy dog.");
out.write("work is like a capricious lover whose ");
out.write("incessant demands are resented but who is missed terribly when she is not there\n");
out.close(); // If you do not close the file, the file stays in the buffer zone, Won't be written into "01.txt" Medium
}
}
FileWriter can only write to files, cannot append to files
Writing and appending files with FileWriter
import java.io.IOException;
import java.io.FileWriter;
public class FileWriterDemo
{
public static void main(String[] args) throws IOException
{
FileWriter out = new FileWriter("02.txt");
//constructor Add to true, I.e. FileWriter out = new FileWriter("02.txt", true) Is to 02.txt The file was appended to the
out.write("work is like a capricious lover whose ");
out.write("incessant demands are resented but who is missed terribly when she is not there\n");
out.write(98.7 + "\n");
out.close(); // It's important, 1 Remember to close the file
}
}
Don't forget
throws IOException