ORMLiteDatabase的简单使用并且与其他的表相互联系

1、下载jar

具体到Android，需要在 http://ormlite.com/releases 页面下载两个jar 包（本文基于ORMLite的版本是：ormlite 4.49-SNAPSHOT）：
（1）core列表下的jar包；
（2）android列表下的jar包。
如图所示：

将上面的两个jar包下载后放到Android工程项目中的libs包中，如图所示：

以上完成后，ORMLite开发环境搭建就完成了，接下来就可以使用了。

2、代码：

表student.java和AClass.java

 1 package com.zzw.ormlitedatabasetest;
 2 
 3 import com.j256.ormlite.field.DatabaseField;
 4 import com.j256.ormlite.table.DatabaseTable;
 5 
 6 @DatabaseTable(tableName = "Student")
 7 public class Student {
 8 
 9     @DatabaseField(id = true, columnName = "Student_id")
10     public int Student_id;
11     @DatabaseField(columnName = "name")
12     public String name;
13     @DatabaseField(columnName = "sex")
14     public String sex;
15     @DatabaseField(columnName = "age")
16     public int age;
17     @DatabaseField(foreign = true, foreignAutoRefresh = true)
18     public AClass aClass;
19 
20     public Student() {
21 
22     }
23 
24     public Student(String name, String sex, int age) {
25         super();
26         this.name = name;
27         this.sex = sex;
28         this.age = age;
29     }
30 
31     @Override
32     public String toString() {
33         return "Student [Student_id=" + Student_id + ", name=" + name + ", sex=" + sex + ", age=" + age + ",className="
34                 + aClass.name + "]";
35     }
36 
37 }
Student
 1 package com.zzw.ormlitedatabasetest;
 2 
 3 import com.j256.ormlite.dao.ForeignCollection;
 4 import com.j256.ormlite.field.DataType;
 5 import com.j256.ormlite.field.DatabaseField;
 6 import com.j256.ormlite.field.ForeignCollectionField;
 7 import com.j256.ormlite.table.DatabaseTable;
 8 
 9 @DatabaseTable(tableName = "Classess")
10 public class AClass {
11 
12     @DatabaseField(id = true, columnName = "classess_id")
13     public int classess_id;
14     @DatabaseField(dataType = DataType.STRING)
15     public String name;
16     @ForeignCollectionField(eager = false)
17     public ForeignCollection<Student> students = null;
18 
19     public AClass() {
20         super();
21     }
22 
23     public AClass(int classess_id, String name, ForeignCollection<Student> students) {
24         super();
25         this.classess_id = classess_id;
26         this.name = name;
27         this.students = students;
28     }
29 
30 }
AClass

ORMLite数据库管理工具类ORMLiteDatabaseHelper.java：

 1 package com.zzw.ormlitedatabasetest;
 2 
 3 import java.sql.SQLException;
 4 
 5 import com.j256.ormlite.android.apptools.OrmLiteSqliteOpenHelper;
 6 import com.j256.ormlite.dao.Dao;
 7 import com.j256.ormlite.support.ConnectionSource;
 8 import com.j256.ormlite.table.TableUtils;
 9 
10 import android.content.Context;
11 import android.database.sqlite.SQLiteDatabase;
12 import android.database.sqlite.SQLiteDatabase.CursorFactory;
13 import android.util.Log;
14 
15 public class OrmLiteDatabaseHelper extends OrmLiteSqliteOpenHelper {
16     private static final String TAG = "OrmLiteDatabaseHelper";
17 
18     public static OrmLiteDatabaseHelper mDatabaseHelper = null;
19 
20     public Dao<Student, Integer> mStudentDao = null;
21     public Dao<AClass, Integer> mAClassDao = null;
22 
23     public static String database_NAME = "school.db";
24     public static int database_VERSION = 1;
25 
26     public OrmLiteDatabaseHelper(Context context, String databaseName, CursorFactory factory, int databaseVersion) {
27         super(context, databaseName, factory, databaseVersion);
28     }
29 
30     public static OrmLiteDatabaseHelper getInstance(Context context) {
31         if (mDatabaseHelper == null) {
32             mDatabaseHelper = new OrmLiteDatabaseHelper(context, database_NAME, null, database_VERSION);
33         }
34         Log.d(TAG, "数据库school.db创建成功");
35         return mDatabaseHelper;
36     }
37 
38     @Override
39     public void onCreate(SQLiteDatabase arg0, ConnectionSource arg1) {
40         try {
41             TableUtils.createTableIfNotExists(arg1, AClass.class);
42             Log.e(TAG, "AClass表在School.db中被创建");
43             TableUtils.createTableIfNotExists(arg1, Student.class);
44             Log.e(TAG, "Student表在School.db中被创建");
45         } catch (SQLException e) {
46             e.printStackTrace();
47         }
48 
49     }
50 
51     @Override
52     public void onUpgrade(SQLiteDatabase arg0, ConnectionSource arg1, int arg2, int arg3) {
53 
54     }
55 
56     public Dao<Student, Integer> getStudentDao() {
57         if (mStudentDao == null) {
58             try {
59                 mStudentDao = getDao(Student.class);
60                 Log.e(TAG, "得到Student的Dao");
61             } catch (SQLException e) {
62                 e.printStackTrace();
63             }
64         }
65         return mStudentDao;
66     }
67 
68     public Dao<AClass, Integer> getAClassDao() {
69         if (mAClassDao == null) {
70             try {
71                 mAClassDao = getDao(AClass.class);
72                 Log.e(TAG, "得到AClass的Dao");
73             } catch (SQLException e) {
74                 e.printStackTrace();
75             }
76         }
77         return mAClassDao;
78     }
79 
80     @Override
81     public void close() {
82         super.close();
83         if (mAClassDao != null) {
84             mAClassDao = null;
85         }
86         if (mStudentDao != null) {
87             mStudentDao = null;
88         }
89     }
90 }

MainActivity:

  1 package com.zzw.ormlitedatabasetest;
  2 
  3 import java.sql.SQLException;
  4 import java.util.List;
  5 
  6 import com.j256.ormlite.dao.Dao;
  7 
  8 import android.app.Activity;
  9 import android.graphics.Color;
 10 import android.os.Bundle;
 11 import android.util.Log;
 12 import android.widget.ScrollView;
 13 import android.widget.TextView;
 14 import android.widget.Toast;
 15 
 16 public class MainActivity extends Activity {
 17 
 18     private static final String TAG = "MainActivity";
 19 
 20     private Dao<AClass, Integer> mAClassDao = null;
 21     private Dao<Student, Integer> mStudentDao = null;
 22 
 23     AClass aClass1, aClass2, aClass3, aClass4, aClass5;
 24 
 25     @Override
 26     protected void onCreate(Bundle savedInstanceState) {
 27         super.onCreate(savedInstanceState);
 28         setContentView(R.layout.activity_main);
 29 
 30         OrmLiteDatabaseHelper mOrmLiteDatabaseHelper = OrmLiteDatabaseHelper.getInstance(this);
 31 
 32         mAClassDao = mOrmLiteDatabaseHelper.getAClassDao();
 33         mStudentDao = mOrmLiteDatabaseHelper.getStudentDao();
 34 
 35     }
 36 
 37     @Override
 38     protected void onStart() {
 39         Log.d(TAG, ">>>>>>>>>>>>");
 40         super.onStart();
 41         int AClasses_count = createAClasses();
 42         if (AClasses_count == 5) {
 43             try {
 44                 aClass1 = mAClassDao.queryForId(1);
 45                 aClass2 = mAClassDao.queryForId(2);
 46                 aClass3 = mAClassDao.queryForId(3);
 47                 aClass4 = mAClassDao.queryForId(4);
 48                 aClass5 = mAClassDao.queryForId(5);
 49 
 50                 createStudents();
 51 
 52             } catch (Exception e) {
 53                 e.printStackTrace();
 54             }
 55         } else {
 56             Toast.makeText(this, "班级创建错误", 0).show();
 57         }
 58         queryAllStudents();
 59     }
 60 
 61     private void createStudents() {
 62         Log.d(TAG, "学生创建开始------>");
 63         Student student = new Student();
 64         for (int i = 1; i <= 20; i++) {
 65             student.Student_id = i;
 66             student.age = (int) (Math.random() * 100);
 67             if (i % 2 == 0) {
 68                 student.sex = "男";
 69             } else {
 70                 student.sex = "女";
 71             }
 72             if (i > 0 && i <= 4) {
 73                 student.aClass = aClass1;
 74                 student.name = "陶" + i;
 75             } else if (i > 4 && i <= 8) {
 76                 student.aClass = aClass2;
 77                 student.name = "李" + i;
 78             } else if (i > 8 && i <= 12) {
 79                 student.aClass = aClass3;
 80                 student.name = "阿" + i;
 81             } else if (i > 12 && i <= 16) {
 82                 student.aClass = aClass4;
 83                 student.name = "曾" + i;
 84             } else {
 85                 student.aClass = aClass5;
 86                 student.name = "蒋" + i;
 87             }
 88 
 89             try {
 90                 mStudentDao.createIfNotExists(student);
 91             } catch (SQLException e) {
 92                 e.printStackTrace();
 93             }
 94         }
 95         Log.d(TAG, "学生创建成功------>");
 96     }
 97 
 98     private int createAClasses() {
 99         Log.d(TAG, "班级创建开始------>");
100         AClass aClass = new AClass();
101         int AClasses_count = 0;
102         for (int i = 1; i <= 5; i++) {
103             aClass.classess_id = i;
104             aClass.name = "高三" + i + "班";
105             try {
106                 mAClassDao.createIfNotExists(aClass);
107                 AClasses_count++;
108             } catch (SQLException e) {
109                 e.printStackTrace();
110             }
111         }
112         Log.d(TAG, "班级创建成功------>");
113         return AClasses_count;
114     }
115 
116     private void queryAllStudents() {
117         Log.d(TAG, "查询全部学生开始------>>>>");
118         try {
119             List<Student> students = mStudentDao.queryForAll();
120             if (students != null && students.size() > 0) {
121                 for (Student student : students) {
122                     Log.i(TAG, student.toString());
123                 }
124             }
125         } catch (SQLException e) {
126             e.printStackTrace();
127         }
128         Log.d(TAG, "查询全部学生完毕------>>>>");
129     }
130 
131     @Override
132     protected void onDestroy() {
133         super.onDestroy();
134         if (mAClassDao != null) {
135             mAClassDao = null;
136         }
137         if (mStudentDao != null) {
138             mStudentDao = null;
139         }
140         Log.d(TAG, "<<<<<<<<<<<");
141     }
142 
143 }
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原文地址：https://www.cnblogs.com/zzw1994/p/4956718.html