SQLite

用户保存常量的类

public class Person_constant {    public final static String TABLE_NAME_PERSON = "t_person";    public final static String TABLE_NAME_PERSON_id = "id";    public final static String TABLE_NAME_PERSON_NAME = "name";    public final static String TABLE_NAME_PERSON_AGE = "age";}

用户保存数据Person类

public class Person {    private int id;    private String name;    private int age;    public Person() {    }    public Person(int id, String name, int age) {        this.id = id;        this.name = name;        this.age = age;    }    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;    }    public int getAge() {        return age;    }    public void setAge(int age) {        this.age = age;    }    @Override    public String toString() {        return "Person{" +                "id=" + id +                ", name='" + name + '\'' +                ", age=" + age +                '}';    }}

工具类

public class SQLiteOpenHelperDemo extends SQLiteOpenHelper {    private static SQLiteOpenHelperDemo sqLiteOpenHelperDemo;    private final static String DATABASE_NAME = "MyDataBase.db";    private final static int VERSION = 1;    private SQLiteOpenHelperDemo(Context context) {        super(context, DATABASE_NAME, null, VERSION);        System.out.println(sqLiteOpenHelperDemo);    }    public static SQLiteOpenHelperDemo getInstance(Context context) {        if (sqLiteOpenHelperDemo == null) {            sqLiteOpenHelperDemo = new SQLiteOpenHelperDemo(context);        }        return sqLiteOpenHelperDemo;    }    @Override    public void onCreate(SQLiteDatabase db) {        StringBuffer creat_table = new StringBuffer();        creat_table.append("CREATE TABLE IF NOT EXISTS ")                .append(Person_constant.TABLE_NAME_PERSON)                .append("(")                .append(Person_constant.TABLE_NAME_PERSON_id)                .append(" INTEGER PRIMARY KEY AUTOINCREMENT,")                .append(Person_constant.TABLE_NAME_PERSON_NAME)                .append(" VARCHAR(20) UNIQUE,")                .append(Person_constant.TABLE_NAME_PERSON_AGE)                .append(" INTEGER DEFAULT 1 CHECK(age BETWEEN 1 AND 150))");        db.execSQL(creat_table.toString());        StringBuffer insert_table=new StringBuffer();        insert_table.append("INSERT INTO ")        .append(Person_constant.TABLE_NAME_PERSON)        .append(" VALUES")        .append("(null,?,?)");        db.execSQL(insert_table.toString(),new Object[]{"张三",20});        db.execSQL(insert_table.toString(),new Object[]{"李四",21});        db.execSQL(insert_table.toString(),new Object[]{"王五",22});    }    @Override    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {    }}

接口类`

public interface DAO {    void insert(Person person);    void update(Person person);    void delete(Person person);    List<Person> select();    List<Person> select(Integer... id);    List<Person> select(String... name);}实现接口的业务类

//
// long insert(String table,String nullColumnHack,ContentValues values)
// table:插入的表名
// nullColumnHack:当values为null或者size()为0时，强行null时的是数据列列名，不能是主键与非空列
// values:插入的一行记录数据，内部封装了HashMap
//
//update(String table,ContentValues values,String whereClause,String[] whereArgs)
// table:要更新的表名
// values：要更新的数据，内部封装了HashMap
// whereClause:满足该条件的记录会被更新(占位符)
// whereArgs：为whereArgs字句传入参数(代替占位符)
//
//delete(String table,String whereClause,String[] whereArgs)
// table:要删除的表名
// whereClause：满足该条件的记录会被删除（占位符）
// whereArgs:为whereClause传入参数(代替占位符)
//
//Cursor query(boolean distinct,是否要去除重复记录
// String table,要查询数据的表名
// String[] columns,要查询的列名
// String whereClause,查询条件子条件（占位符）
// String[] selectionArgs,为占位符传入参数
// String groupBy,控制分组
// String having,对分组过滤
// String orderBy,对记录排序
// String limit)进行分页
//
//
public class DAOBean implements DAO {
private SQLiteOpenHelperDemo sqLiteOpenHelperDemo;

public DAOBean(Context context) {    this.sqLiteOpenHelperDemo = SQLiteOpenHelperDemo.getInstance(context);}@Overridepublic void insert(Person person) {    SQLiteDatabase db = sqLiteOpenHelperDemo.getWritableDatabase();

// String insert_table =
// “INSERT INTO ”
// + Person_constant.TABLE_NAME_PERSON
// + ” VALUES(null,?,?)”;
// db.execSQL(insert_table, new Object[]{person.getName(), person.getAge()});
ContentValues contentValues=new ContentValues();
contentValues.put(“id”,person.getId());
contentValues.put(“name”,person.getName());
contentValues.put(“age”,person.getAge());
db.insert(Person_constant.TABLE_NAME_PERSON,null,contentValues);

}@Overridepublic void update(Person person) {    SQLiteDatabase db = sqLiteOpenHelperDemo.getWritableDatabase();    String update = "UPDATE "            + Person_constant.TABLE_NAME_PERSON            + " SET "            + Person_constant.TABLE_NAME_PERSON_NAME            + "=?,"            + Person_constant.TABLE_NAME_PERSON_AGE            + "=?"            + " WHERE "            + Person_constant.TABLE_NAME_PERSON_id            + "=?";    db.execSQL(update, new Object[]{person.getName(), person.getAge(), person.getId()});}@Overridepublic void delete(Person person) {    SQLiteDatabase db = sqLiteOpenHelperDemo.getWritableDatabase();    String delete = "DELETE FROM "            + Person_constant.TABLE_NAME_PERSON            + " WHERE "            + Person_constant.TABLE_NAME_PERSON_id            + "=?";    db.execSQL(delete, new Object[]{person.getId()});}@Overridepublic List<Person> select() {    SQLiteDatabase db = sqLiteOpenHelperDemo.getWritableDatabase();    String selectAll = "SELECT *FROM " + Person_constant.TABLE_NAME_PERSON;    List<Person> list = new ArrayList<>();    Cursor cursor = null;    try {        cursor = db.rawQuery(selectAll, null);        while (cursor.moveToNext()) {            Person person = new Person(                    cursor.getInt(cursor.getColumnIndex("id")),                    cursor.getString(cursor.getColumnIndex("name")),                    cursor.getInt(cursor.getColumnIndex("age"))            );            list.add(person);        }        return list;    } catch (Exception e) {        e.printStackTrace();    } finally {        if (db != null && db.isOpen()) {            db.close();            db = null;        }        if (cursor != null && !cursor.isClosed()) {            cursor.close();            cursor = null;        }    }    return null;}@Overridepublic List<Person> select(Integer... id) {    SQLiteDatabase db = sqLiteOpenHelperDemo.getWritableDatabase();    List<Person> list = new ArrayList<>();    StringBuffer sb = new StringBuffer();    for (int ids : id) {        sb.append("?,");    }    sb.deleteCharAt(sb.length() - 1);    String select = "SELECT *FROM "            + Person_constant.TABLE_NAME_PERSON            + " WHERE id in (" + sb.toString() + ")";    String[] st = new String[id.length];    for (int i = 0; i < id.length; i++) {        st[i] = String.valueOf(id[i]);    }    Cursor cursor = null;    try {        cursor = db.rawQuery(select, st);        while (cursor.moveToNext()) {            Person p = new Person(                    cursor.getInt(cursor.getColumnIndex("id")),                    cursor.getString(cursor.getColumnIndex("name")),                    cursor.getInt(cursor.getColumnIndex("age"))            );            list.add(p);        }        return list;    } catch (Exception e) {        e.printStackTrace();    } finally {        if (db != null && db.isOpen()) {            db.close();            db = null;        }        if (cursor != null && !cursor.isClosed()) {            cursor.close();            cursor = null;        }    }    return null;}@Overridepublic List<Person> select(String... name) {    List<Person> list = new ArrayList<>();    SQLiteDatabase db = sqLiteOpenHelperDemo.getWritableDatabase();    StringBuffer sb = new StringBuffer();    for (String names : name) {        sb.append("?,");    }    sb.deleteCharAt(sb.length() - 1);    String selectName = "SELECT *FROM "            + Person_constant.TABLE_NAME_PERSON            + " WHERE name in (" + sb.toString() + ")";    Cursor cursor = null;    try {        cursor = db.rawQuery(selectName, name);        while (cursor.moveToNext()) {            Person p = new Person(                    cursor.getInt(cursor.getColumnIndex("id")),                    cursor.getString(cursor.getColumnIndex("name")),                    cursor.getInt(cursor.getColumnIndex("age"))            );            list.add(p);        }        return list;    } catch (Exception e) {        e.printStackTrace();    } finally {        if (db != null && db.isOpen()) {            db.close();            db = null;        }        if (cursor != null && !cursor.isClosed()) {            cursor.close();            cursor = null;        }    }    return null;}@Overridepublic List<Person> selectPagination(int pageNo, int pageSize) {    return null;}

}