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Ormlite的简单使用详解

Ormlite的简单使用详解

作者: OneXzgj | 来源:发表于2017-07-13 17:35 被阅读181次
    package com.example.ormdb;
    
    import android.content.Context;
    import android.database.sqlite.SQLiteDatabase;
    
    import com.example.ormdb.bean.Person;
    import com.j256.ormlite.android.apptools.OrmLiteSqliteOpenHelper;
    import com.j256.ormlite.dao.Dao;
    import com.j256.ormlite.support.ConnectionSource;
    import com.j256.ormlite.table.TableUtils;
    
    import java.sql.SQLException;
    import java.util.HashMap;
    import java.util.Map;
    
    
    /**
     * Created by Linsa on 2017/7/13.
     */
    
    public class MyDbHelper extends OrmLiteSqliteOpenHelper {
    
        private static final int DB_VERSION=1;
        private static final String DB_NAME="person.db3";
    
    
        /**
         * 用来存放Dao的地图
         */
        private Map<String, Dao> daos = new HashMap<String, Dao>();
    
        private static MyDbHelper instance;
    
        public MyDbHelper(Context context) {
            super(context, DB_NAME, null, DB_VERSION);
        }
    
        @Override
        public void onCreate(SQLiteDatabase sqLiteDatabase, ConnectionSource connectionSource) {
            try {
    //            TableUtils.createTable(connectionSource,Student.class);
                TableUtils.createTable(connectionSource,Person.class);
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    
        @Override
        public void onUpgrade(SQLiteDatabase sqLiteDatabase, ConnectionSource connectionSource, int i, int i1) {
    
        }
    
        public synchronized  Dao getDao(Class clazz) throws SQLException {
            Dao dao=null;
            String simpleName = clazz.getSimpleName();
            if (daos.containsKey(simpleName)) {
                dao = daos.get(simpleName);
    
            }else{
                dao = super.getDao(clazz);
                daos.put(simpleName,dao);
            }
            return dao;
        }
    
    
        /**
         * 获取一个数据库的单实例
         * @param context
         * @return
         */
        public MyDbHelper getInstance(Context context){
            context = context.getApplicationContext();
            if (instance==null){
                synchronized (MyDbHelper.class) {
                    if (instance==null) {
                        instance = new MyDbHelper(context);
                    }
                }
            }
            return instance;
        }
    
    
        @Override
        public void close() {
            super.close();
            for (String key:daos.keySet()) {
                Dao dao = daos.get(key);
                dao=null;
            }
        }
    }
    
    

    PersonDao.class文件的详细信息,数据库操作的中间层

    package com.example.ormdb.dao;
    
    import android.content.Context;
    
    import com.example.ormdb.MyDbHelper;
    import com.example.ormdb.bean.Person;
    import com.j256.ormlite.dao.Dao;
    
    import java.sql.SQLException;
    import java.util.ArrayList;
    import java.util.List;
    
    /**
     * Created by Linsa on 2017/7/13.
     */
    
    
    public class PersonDao {
    
        private  Dao mPersonDao;
    
        public PersonDao(Context context)  {
            try {
                mPersonDao = new MyDbHelper(context).getDao(Person.class);
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    
        /**
         * 向数据库中添加一条数据
         * @param person
         */
        public void add(Person person){
            try {
                mPersonDao.create(person);
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    
        /**
         * 删除一条数据
         * @param person
         */
        public void delete(Person person){
            try {
                mPersonDao.delete(person);
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    
    
        /**
         * 删除一组数据
         */
        public void deleteCollection(ArrayList<Person> arrayList){
            try {
                mPersonDao.delete(arrayList);
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    
        /**
         * 查询一条记录
         * @param id
         * @return
         */
        public Person queryForId(int id) {
            Person person = null;
            try {
                person = (Person) mPersonDao.queryForId(id);
            } catch (SQLException e) {
                e.printStackTrace();
            }
            return person;
        }
    
    
        /**
         * 查询所有记录
         * @return
         */
        public List<Person> queryForAll() {
            List<Person> themes = new ArrayList<Person>();
            try {
          
          themes = mPersonDao.queryForAll();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            return themes;
        }
    
    
    
    }
    
    

    数据Bean的详细代码

    package com.example.ormdb.bean;
    
    import com.j256.ormlite.field.DatabaseField;
    import com.j256.ormlite.table.DatabaseTable;
    
    import java.io.Serializable;
    
    /**
     * Created by Linsa on 2017/7/13.
     */
    
    @DatabaseTable
    public class Person implements Serializable {
    
        //这里的这个属性是自增的属性,当设置了这个属性以后,默认也就是认定这个属性为主键,如果再设置 id=true的话,则会进行报错
        //java.lang.IllegalArgumentException: Must specify one of id, generatedId, and generatedIdSequence with id
        @DatabaseField(id =true,generatedId = true)
        public int id;
        @DatabaseField
        public String name;
        @DatabaseField
        public int age;
        @DatabaseField
        public String sex;
    
        @Override
        public String toString() {
            return "Person{" +
                    "id='" + id + '\'' +
                    ", name='" + name + '\'' +
                    ", age=" + age +
                    ", sex='" + sex + '\'' +
                    '}';
        }
    }
    
    

    MainActivity.java的详细代码

    package com.example.ormdb;
    
    import android.os.Bundle;
    import android.support.v7.app.AppCompatActivity;
    import android.view.View;
    import android.widget.Button;
    import android.widget.Toast;
    
    import com.example.ormdb.bean.Person;
    import com.example.ormdb.dao.PersonDao;
    
    import java.util.List;
    
    import butterknife.ButterKnife;
    import butterknife.InjectView;
    import butterknife.OnClick;
    
    public class MainActivity extends AppCompatActivity {
    
        @InjectView(R.id.btn_querry)
        Button btnQuerry;
        @InjectView(R.id.btn_add)
        Button btnAdd;
        @InjectView(R.id.btn_delete)
        Button btnDelete;
    
        private int i = 0;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            ButterKnife.inject(this);
        }
    
        @OnClick({R.id.btn_add, R.id.btn_querry, R.id.btn_delete})
        public void onViewClicked(View view) {
            switch (view.getId()) {
                case R.id.btn_add:
                    Person person = new Person();
                    person.name = "onex" + i;
                    person.sex = "女";
    
                    new PersonDao(MainActivity.this).add(person);
                    i++;
                    Toast.makeText(MainActivity.this, "add success", Toast.LENGTH_SHORT).show();
                    break;
                case R.id.btn_querry:
                    List<Person> persons = new PersonDao(MainActivity.this).queryForAll();
                    for (Person p : persons) {
                        Toast.makeText(MainActivity.this, p.toString(), Toast.LENGTH_SHORT).show();
                    }
    
                    break;
                case R.id.btn_delete:
    
                    //设置删除的时候只要设置对象的一个id就可以
                    //设置其他的属性也是可以的
    
                    Person delPer = new Person();
                    delPer.id=5;
    //                delPer.name="onex3";
    //                delPer.sex="女";
                    new PersonDao(MainActivity.this).delete(delPer);
    
                    Toast.makeText( MainActivity.this, "delete success!", Toast.LENGTH_SHORT).show();
                    break;
            }
        }
    
        @Override
        protected void onDestroy() {
            super.onDestroy();
            new MyDbHelper(MainActivity.this).close();
        }
    }
    
    

    数据库jar包的下载和使用:
    jar包下载地址 :http://ormlite.com/releases/
    具体下载如下图所示:

    UOUCCM{6WGZ)TMELJ$JUFPL.png

    具体的可以查看官方文档 :http://ormlite.com/javadoc/ormlite-android/

    参考范文:http://blog.csdn.net/lmj623565791/article/details/39122981

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