SQLite additions and deletions to search

First step: Create a class to inherit sqliteopenhelper.

The OnCreate method connects the database for the first time to execute

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Step Two: Create the entity class person.

Package com.jasper.SQLite.entities;

public class Person {

private int id;

private String name;

private int age;

Public person () {

Super ();

}

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.) {

This.age = age;

}

public person (int ID, String name, int age) {

Super ();

This.id = ID;

THIS.name = name;

This.age = age;

}

@Override

Public String toString () {

return "person [id=" + ID + ", name=" + name + ", age=" + Age + "]";

}

}

Step three: Create a database operation class Persondao

Package Com.jasper.SQLite.dao;

Import java.util.ArrayList;

Import java.util.List;

Import Com.jasper.SQLite.db.PersonSQLiteOpenHelper;

Import Com.jasper.SQLite.entities.Person;

Import Android.content.Context;

Import Android.database.Cursor;

Import Android.database.sqlite.SQLiteDatabase;

public class Persondao {

Private Personsqliteopenhelper Mopenhelper;

Public Persondao (Context context) {

Mopenhelper = new Personsqliteopenhelper (context);

}

Inserting data into the persons table

public void Insert (person p) {

Sqlitedatabase db = Mopenhelper.getwritabledatabase ();

if (Db.isopen ()) {

Insert operation

Db.execsql ("INSERT into persons (Name,age) values (?,?);",

New object[] {p.getname (), P.getage ()});

Close the database

Db.close ();

}

}

public void Delete (int id) {

Sqlitedatabase db = Mopenhelper.getwritabledatabase ();

if (Db.isopen ()) {

Delete operation

Db.execsql ("Delete from persons where id =?;",

New integer[] {ID});

Close the database

Db.close ();

}

}

public void Update (String name, int id) {

Sqlitedatabase db = Mopenhelper.getwritabledatabase ();

if (Db.isopen ()) {

Update action

Db.execsql ("update persons set name =?") where id =?; ",

New object[] {name, id});

Close the database

Db.close ();

}

Db.close ();

}

Querying the entire sheet

Public list<person> Queryall () {

Sqlitedatabase db = Mopenhelper.getwritabledatabase ();

if (Db.isopen ()) {

Query operations

cursor cursor = db.rawquery ("Select id,name,age from Persons;",

NULL);

The result set is not empty and the entry is greater than 0

if (cursor! = NULL && cursor.getcount () > 0) {

list<person> personlist = new arraylist<person> ();

int id;

String name;

int age;

while (Cursor.movetonext ()) {

id = cursor.getint (0);

Name = cursor.getstring (1);

Age = Cursor.getint (2);

Personlist.add (new person (ID, name, age));

}

Close the database

Db.close ();

return personlist;

}

Db.close ();

}

return null;

}

Public person query (int id)

{

Sqlitedatabase db = Mopenhelper.getwritabledatabase ();

if (Db.isopen ()) {

cursor cursor = db.rawquery ("Select id,name,age from persons where id =?;", New String[]{id + ""});

if (cursor! = NULL && cursor.movetofirst ())

{

int _id = cursor.getint (0);

String name = cursor.getstring (1);

int age = Cursor.getint (2);

Db.close ();

return new person (_id, name, age);

}

Db.close ();

}

return null;

}

}

Fourth step: Create a Test class TestCase

Package com.jasper.SQLite.test;

Import java.util.List;

Import Com.jasper.SQLite.dao.PersonDao;

Import Com.jasper.SQLite.db.PersonSQLiteOpenHelper;

Import Com.jasper.SQLite.entities.Person;

Import Android.test.AndroidTestCase;

Import Android.util.Log;

public class TestCase extends Androidtestcase {

private static final String TAG = "TestCase";

public void Test ()

{

Personsqliteopenhelper openhelper = new Personsqliteopenhelper (GetContext ());

Openhelper.getwritabledatabase ();

}

public void Testinsert ()

{

Persondao per = new Persondao (GetContext ());

Per.insert (new person (0, "punk", 20));

}

public void Testdelete ()

{

Persondao per = new Persondao (GetContext ());

Per.delete (2);

}

public void Testupdate ()

{

Persondao per = new Persondao (GetContext ());

Per.update ("Lily", 1);

}

public void Testqueryall ()

{

Persondao per = new Persondao (GetContext ());

list<person> personlist = Per.queryall ();

for (person Person:personlist) {

LOG.I (TAG, person.tostring ());

}

}

public void Testquery ()

{

Persondao per = new Persondao (GetContext ());

Person person = per.query (1);

LOG.I (TAG, person.tostring ());

}

}

SQLite additions and deletions to search