sqlite一些基本的操作
sqlite属于一种嵌入式的数据库，并不像其他数据库要安装服务器端，只要安装android模拟器就可以对sqlite操作了。
首先写一个数据库的工具类
importandroid.content.Context;
importandroid.database.sqlite.SQLiteDatabase;
importandroid.database.sqlite.SQLiteOpenHelper;
publicclassDataBaseHeplerextendsSQLiteOpenHelper{
privatestaticfinalStringname="sharp.db";
privatestaticfinalintversion=1;
publicDataBaseHepler(Contextcontext){
super(context,NAME,null,version);
}
@Override
publicvoidonCreate(SQLiteDatabasedb){
db.execSQL("createtableperson(personidintegerprimarykeyautoincrement,namevarchar(20),ageinteger)");
}
@Override
publicvoidonUpgrade(SQLiteDatabasedb,intoldVersion,intnewVersion){
}
}
只需要在里面添加表就可以了
然后添加一个对象
publicclassPerson{
privateIntegerid;
privateStringname;
privateIntegerage;
publicPerson(Integerid,Stringname,Integerage){
super();
this.id=id;
this.name=name;
this.age=age;
}
publicIntegergetId(){
returnid;
}
publicvoidsetId(Integerid){
this.id=id;
}
publicStringgetName(){
returnname;
}
publicvoidsetName(Stringname){
this.name=name;
}
publicIntegergetAge(){
returnage;
}
publicvoidsetAge(Integerage){
this.age=age;
}
publicPerson(Stringname,Integerage){
super();
this.name=name;
this.age=age;
}
publicPerson(){
super();
}
publicStringtoString(){
return"id="+id+"name="+name+"age="+age;
}
}
之后写一个service类，里面包含数据库的一些基本的操作
importjava.util.ArrayList;
importjava.util.List;
importcom.sharpandroid.domain.Person;
importandroid.content.Context;
importandroid.database.Cursor;
importandroid.database.sqlite.SQLiteDatabase;
publicclassPersonService{
privateContextcontext;
privateDataBaseHeplerdataBaseHepler;
publicPersonService(Contextcontext){
this.context=context;
dataBaseHepler=newDataBaseHepler(context);
}
publicvoidsave(Personperson){
SQLiteDatabasedatabase=dataBaseHepler.getWritableDatabase();
database.execSQL("insertintoperson(name,age)values(?,?)",newObject[]{person.getName(),person.getAge()});
}
publicvoidupdate(Personperson){
SQLiteDatabasedatabase=dataBaseHepler.getWritableDatabase();
database.execSQL("updatepersonsetname=?,age=?wherepersonid=?",newObject[]{person.getName(),person.getAge(),person.getId()});
}
publicPersonfind(Integerid){
SQLiteDatabasedatabase=dataBaseHepler.getWritableDatabase();
Cursorcursor=database.rawQuery("selectpersonid,name,agefrompersonwherepersonid=?",newString[]{String.valueOf(id)});
if(cursor.moveToNext()){
Personperson=newPerson();
person.setId(cursor.getInt(cursor.getColumnIndex("personid")));
person.setName(cursor.getString(1));
person.setAge(cursor.getInt(2));
returnperson;
}
cursor.close();
returnnull;
}
publicvoiddelete(Integerid){
SQLiteDatabasedatabase=dataBaseHepler.getWritableDatabase();
database.execSQL("deletefrompersonwherepersonid=?",newObject[]{id});
}
publiclonggetCount(){
SQLiteDatabasedatabase=dataBaseHepler.getWritableDatabase();
Cursorcursor=database.rawQuery("selectcount(*)fromperson",null);
cursor.moveToFirst();
longcount=cursor.getLong(0);
cursor.close();
returncount;
}
}
在AndroidManifest.xml添加测试类
<?xmlversion="1.0"encoding="utf-8"?>
<manifestxmlns:android="http://schemas.android.com/apk/res/android"
package="com.android.activity"
android:versionCode="1"
android:versionname="1.0">
<applicationandroid:icon="@drawable/icon"android:label="@string/app_name">
<uses-libraryandroid:name="android.test.runner"/>
<activityandroid:name=".PersonActivity"
android:label="@string/app_name">
<intent-filter>
<actionandroid:name="android.intent.action.MAIN"/>
<categoryandroid:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
</application>
<instrumentationandroid:name="android.test.InstrumentationTestRunner"android:targetPackage="com.sharpandroid.activity"android:label="TestforMyApp"/>
</manifest>
之后写一个测试单元就可以进行测试了
publicclassPersonServiceTestextendsAndroidTestCase{
publicvoidtestSave()throwsThrowable{
PersonServicepersonService=newPersonService(this.getContext());
Personperson=newPerson("Tom",21);
personService.save(person);
}
}
要想看执行之后生成的数据库可以用FileExplorer视图就可以看到生成之后的数据库文件，可以把生成之后的数据库导出来导入到sqlite可视化工具，就可以查看里面的数据，也可以用adb命令查看表中的数据