标签:android c class blog code java
知识点详解:http://blog.csdn.net/zhaoyazhi2129/article/details/9025995
具体代码:
package com.example.android_sqlite; import android.app.Activity; import android.os.Bundle; import com.example.android_sqlite.dao.impl.UserDaoImpls; import com.example.android_sqlite.database.DatabaseHelper; public class MainActivity extends Activity { private UserDaoImpls userDaoImpls; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); // 创建数据库 DatabaseHelper dh = new DatabaseHelper(this); userDaoImpls = new UserDaoImpls(dh); } }
package com.example.android_sqlite.domain; import java.io.Serializable; public class Users implements Serializable{ private static final long serialVersionUID = 1L; private Integer userId; private String userName; private Integer userAge; private Double userSalary; public Users() { super(); } public Users(Integer userId, String userName, Integer userAge, Double userSalary) { super(); this.userId = userId; this.userName = userName; this.userAge = userAge; this.userSalary = userSalary; } public Integer getUserId() { return userId; } public void setUserId(Integer userId) { this.userId = userId; } public String getUserName() { return userName; } public void setUserName(String userName) { this.userName = userName; } public Integer getUserAge() { return userAge; } public void setUserAge(Integer userAge) { this.userAge = userAge; } public Double getUserSalary() { return userSalary; } public void setUserSalary(Double userSalary) { this.userSalary = userSalary; } @Override public String toString() { return "Users [userId=" + userId + ", userName=" + userName + ", userAge=" + userAge + ", userSalary=" + userSalary + "]"; } }
package com.example.android_sqlite.dao; import java.util.List; public interface BaseDao<T, PK> { /** * 插入实体对象 * * @param entity * @return */ public boolean insert(T entity); /** * 更新实体对象 * * @param entity * @return */ public boolean update(T entity); /** * 删除实体对象 * * @param entity * @return */ public boolean delete(T entity); /** * 根据id删除对象 * * @param id * @return */ public boolean deleteByid(PK id); /** * 根据id查找对象 * * @param id * @return */ public T findByid(PK id); /** * 查找所有 * * @return */ public List<T> findAll(); }
package com.example.android_sqlite.dao; import com.example.android_sqlite.domain.Users; public interface UserDao extends BaseDao<Users, Integer>{ }
package com.example.android_sqlite.dao.impl; import java.util.ArrayList; import java.util.List; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import com.example.android_sqlite.dao.UserDao; import com.example.android_sqlite.database.DatabaseHelper; import com.example.android_sqlite.domain.Users; public class UserDaoImpls implements UserDao { // 依赖对象 private DatabaseHelper dh; // 通过数据库的构造器实例化 public UserDaoImpls(DatabaseHelper databaseHelper) { this.dh = databaseHelper; } @Override public boolean insert(Users entity) { // 得到数据库操作对象 try { SQLiteDatabase db = dh.getWritableDatabase(); /* * 方法一 * db.execSQL("insert into users(username,userage,usersalary) values('" * + entity.getUserName() + "'," + entity.getUserAge() + "," + * entity.getUserSalary() + ")"); */ // 方法二 db.execSQL( "insert into users(username,userage,usersalary) values(?,?,?)", new Object[] { entity.getUserName(), entity.getUserAge(), entity.getUserSalary() }); db.close(); } catch (Exception e) { e.printStackTrace(); return false; } return true; } @Override public boolean update(Users entity) { try { SQLiteDatabase db = dh.getWritableDatabase(); db.execSQL( "update users set username=?,userage=?,usersalary=? where userid=?", new Object[] { entity.getUserName(), entity.getUserAge(), entity.getUserSalary(), entity.getUserId() }); db.close(); } catch (Exception e) { e.printStackTrace(); return false; } return true; } @Override public boolean delete(Users entity) { return deleteByid(entity.getUserId()); } @Override public boolean deleteByid(Integer id) { try { SQLiteDatabase db = dh.getWritableDatabase(); db.execSQL("delete from users where userid=?", new Object[] { id }); db.close(); } catch (Exception e) { e.printStackTrace(); return false; } return true; } @Override public Users findByid(Integer id) { Users entity = null; SQLiteDatabase db = dh.getWritableDatabase(); Cursor c = db .rawQuery( "select userid,username,userage,usersalary from users where userid=?", new String[] { id + "" }); if (c.moveToNext()) { entity = new Users(); entity.setUserId(c.getInt(c.getColumnIndex("userid"))); entity.setUserName(c.getString(c.getColumnIndex("userid"))); entity.setUserAge(c.getInt(c.getColumnIndex("userage"))); entity.setUserSalary(c.getDouble(c.getColumnIndex("usersalary"))); } return entity; } @Override public List<Users> findAll() { List<Users> entities = new ArrayList<Users>(); SQLiteDatabase db = dh.getWritableDatabase(); Cursor c = db .rawQuery( "select userid,username,userage,usersalary from users", null); while (c.moveToNext()) { Users entity = new Users(); entity.setUserId(c.getInt(c.getColumnIndex("userid"))); entity.setUserName(c.getString(c.getColumnIndex("userid"))); entity.setUserAge(c.getInt(c.getColumnIndex("userage"))); entity.setUserSalary(c.getDouble(c.getColumnIndex("usersalary"))); entities.add(entity); } return entities; } }
package com.example.android_sqlite.test; import java.util.List; import com.example.android_sqlite.dao.UserDao; import com.example.android_sqlite.dao.impl.UserDaoImpls; import com.example.android_sqlite.database.DatabaseHelper; import com.example.android_sqlite.domain.Users; import android.test.AndroidTestCase; public class DatabaseTeses extends AndroidTestCase { public void createDatabase() { DatabaseHelper dh = new DatabaseHelper(getContext()); dh.getWritableDatabase(); } public void insert() { DatabaseHelper databaseHelper = new DatabaseHelper(getContext()); UserDao userDao = new UserDaoImpls(databaseHelper); Users entity = new Users(null, "iii2", 20, 4000.0); boolean flag = userDao.insert(entity); assertEquals(true, flag); } public void update() { DatabaseHelper databaseHelper = new DatabaseHelper(getContext()); UserDao userDao = new UserDaoImpls(databaseHelper); Users entity = new Users(7, "aaa", 21, 3000.0); boolean flag = userDao.update(entity); assertEquals(true, flag); } public void delete() { DatabaseHelper databaseHelper = new DatabaseHelper(getContext()); UserDao userDao = new UserDaoImpls(databaseHelper); Users entity = new Users(1, "", null, null); boolean flag = userDao.delete(entity); assertEquals(true, flag); } public void findById() { DatabaseHelper databaseHelper = new DatabaseHelper(getContext()); UserDao userDao = new UserDaoImpls(databaseHelper); Users entity = userDao.findByid(3); if (entity != null) { System.out.println(entity.toString()); } else { System.out.println("no message"); } } public void findAll() { DatabaseHelper databaseHelper = new DatabaseHelper(getContext()); UserDao userDao = new UserDaoImpls(databaseHelper); List<Users> entities = userDao.findAll(); for (Users entity : entities) { System.out.println(entity.toString()); } } }
赵雅智_使用SQLiteDatabase操作SQLite数据库及事务,布布扣,bubuko.com
赵雅智_使用SQLiteDatabase操作SQLite数据库及事务
标签:android c class blog code java
原文地址:http://blog.csdn.net/zhaoyazhi2129/article/details/28640195