Android SQLite事务操作

Android SQLite事务操作

1. 新建DBOpenHelper继承自SQLiteOpenHelper类：

public class DBOpenHelper extends SQLiteOpenHelper {

    private final static String DATABASENAME = "itcast.db";
    private final static int DATABASEVERSION = 2;

    public DBOpenHelper(Context context) {
        super(context, DATABASENAME, null, DATABASEVERSION);

    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE person (personid integer primary key autoincrement, name varchar(20))");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        Log.i("old", oldVersion +"");
        Log.i("new", newVersion + "");
        db.execSQL("ALTER TABLE person ADD amount integer");
    }

}

2.新建对应数据库中表的字段的JavaBean数据类：

public class Person {

    private Integer id;
    private String name;
    private Integer amount;

    public Person() {

    }    
    public Person(Integer id, String name, Integer amount) {
        super();
        this.id = id;
        this.name = name;
        this.amount = amount;
    }
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public Integer getAmount() {
        return amount;
    }
    public void setAmount(Integer amount) {
        this.amount = amount;
    }
    @Override
    public String toString() {
        return "Person [id=" + id + ", name=" + name + ", amount=" + amount
                + "]";
    }
}

3. 新建事务操作方法：

public void payment() {
        SQLiteDatabase db = dbHelper.getWritableDatabase();
        db.beginTransaction();
        try {
            db.execSQL("update person set amount=amount-10 where personid=?", new Object[]{1});
            db.execSQL("update person set amount=amount+10 where personid=?", new Object[]{2});
            db.setTransactionSuccessful();
        } finally {
            db.endTransaction();
        }
    }

4.新建单元测试类对业务类中的方法进行测试：

public void testpayment() throws Exception {
        DBService dbService = new DBService(this.getContext());
        dbService.payment();
    }