Android SQLite (add delete change check) operation instance code

Five classes are required:

1. Entity class: Person.java

2. Abstract class: SQLOperate.java (encapsulates operations on the database)

3. Helper class: DBOpenHelper.java (inherited SQLiteOpenHelper)

4. Implementation class: SQLOperateImpl.java (implementation abstract class SQLOperate.java)

5. Test class: Test.java(inherited AndroidTestCase)

1.Person.java

package com.mrzhu.sqltite;
public class Person {

 private int _id;
 private String name;

 public int getId() {
  return _id;
 }

 public void setId(int _id) {
  this._id = _id;
 }

 public String getName() {
  return name;
 }

 public void setName(String name) {
  this.name = name;
 }

 @Override
 public String toString() {
  return "Person [id=" + _id + ", name=" + name + "]";
 }

 public Person() {
  super();
 }

 public Person(int _id, String name) {
  super();
  this._id = _id;
  this.name = name;
 }
}

2.SQLOperate.java

package com.mrzhu.sqltite;
import java.util.List;
/**
 *  Add and delete 
 * @author ZLQ
 *
 */
public interface SQLOperate {
 public void add(Person p);
 public void delete(int id);
 public void updata(Person p);
 public List<Person> find();
 public Person findById(int id);
}

3.DBOpenHelper.java

package com.mrzhu.sqltite;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
/**
 *  Helper classes 
 * @author ZLQ
 *
 */
public class DBOpneHelper extends SQLiteOpenHelper {
 private static final int VERSION = 1;// version 
 private static final String DB_NAME = "people.db";// The database name 
 public static final String STUDENT_TABLE = "student";// The name of the table 
 public static final String _ID = "_id";// The column names in the table 
 public static final String NAME = "name";// The column names in the table 
 // Create a database statement, STUDENT_TABLE . _ID  . NAME Put space before and after 
 private static final String CREATE_TABLE = "create table " + STUDENT_TABLE + " ( " + _ID + " Integer primary key autoincrement," + NAME + " text)";

 public DBOpneHelper(Context context) {
  super(context, DB_NAME, null, VERSION);
 }
 // The first database 1 Called the next time it is created  
 @Override
 public void onCreate(SQLiteDatabase db) {
  db.execSQL(CREATE_TABLE);
 }
 // Called during version upgrade  
 @Override
 public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
 }
}

4.SQLOperateImpl.java

package com.mrzhu.sqltite;
import java.util.ArrayList;
import java.util.List;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
public class SQLOperateImpl implements SQLOperate{
 private DBOpneHelper dbOpenHelper;

 public SQLOperateImpl(Context context) {
  dbOpenHelper = new DBOpneHelper(context);
 }
 /**
  *  Increase, insert Insert data into the database 
  */
 public void add(Person p) {
  SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
  ContentValues values = new ContentValues();
  values.put(DBOpneHelper._ID, p.getId());
  values.put(DBOpneHelper.NAME, p.getName());
  db.insert(DBOpneHelper.STUDENT_TABLE, null, values);
 }
 /**
  *  Delete, by id Delete the data 
  */
 public void delete(int id) {
  SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
  db.delete(DBOpneHelper.STUDENT_TABLE, DBOpneHelper._ID + "=?", new String[]{String.valueOf(id)});
 }
 /**
  *  Change, modify the specification id The data of 
  */
 public void updata(Person p) {
  SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
  ContentValues values = new ContentValues();
  values.put(DBOpneHelper._ID, p.getId());
  values.put(DBOpneHelper.NAME, p.getName());
  db.update(DBOpneHelper.STUDENT_TABLE, values, DBOpneHelper._ID + "=?", new String[]{String.valueOf(p.getId())});
 }
 /**
  *  Look up all the data in the table 
  */
 public List<Person> find() {
  List<Person> persons = null;
  SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
  Cursor cursor = db.query(DBOpneHelper.STUDENT_TABLE, null, null, null, null, null, null);
  if(cursor != null){
   persons = new ArrayList<Person>();
   while(cursor.moveToNext()){
    Person person = new Person();
    int _id = cursor.getInt(cursor.getColumnIndex(DBOpneHelper._ID));
    String name = cursor.getString(cursor.getColumnIndex(DBOpneHelper.NAME));
    person.setId(_id);
    person.setName(name);
    persons.add(person);
   }
  }
  return persons;
 }
 /**
  *  The query id The data of 
  */
 public Person findById(int id) {
  SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
  Cursor cursor = db.query(DBOpneHelper.STUDENT_TABLE, null, DBOpneHelper._ID + "=?", new String[]{String.valueOf(id)}, null, null, null);
  Person person = null;
  if(cursor != null && cursor.moveToFirst()){
   person = new Person();
   int _id = cursor.getInt(cursor.getColumnIndex(DBOpneHelper._ID));
   String name = cursor.getString(cursor.getColumnIndex(DBOpneHelper.NAME));
   person.setId(_id);
   person.setName(name);
  }
  return person;
 }
}

5.Test.java

 

In AndroidManifest. The xml < application > < /application > The add

(targetPackage is the package name of the current project)

 

  < instrumentation

android:targetPackage="com.mrzhu.sqltite"

android:name="android.test.InstrumentationTestRunner" >

< /instrumentation >

 

in < application > < /application > add < uses-library android:name="android.test.runner"/ >

package com.mrzhu.sqltite;
import java.util.List;
import android.test.AndroidTestCase;
import android.util.Log;
public class Test extends AndroidTestCase {
 public void testAdd() throws Exception{
  SQLOperateImpl test = new SQLOperateImpl(getContext());
  Person person = new Person(2, "Peter");
  test.add(person);
 }

 public void testDelete() throws Exception{
  SQLOperateImpl test = new SQLOperateImpl(getContext());
  test.delete(1);
 }

 public void testUpdata() throws Exception{
  SQLOperateImpl test = new SQLOperateImpl(getContext());
  Person person = new Person(1, "Tom");
  test.updata(person);
 }

 public void testFind() throws Exception{
  SQLOperateImpl test = new SQLOperateImpl(getContext());
  List<Person> persons = test.find();
  for (Person person : persons) {
   Log.i("System.out", person.toString());
  }
 }

 public void testFindById() throws Exception{
  SQLOperateImpl test = new SQLOperateImpl(getContext());
  Person person = test.findById(2);
  Log.i("System.out", person.toString());
 }
}