SQlite简介（自己不擅长描述，参考https://blog.csdn.net/yanbober/article/details/45567149）
SQLite是一款轻型的数据库，是关系型数据库（RDBMS）管理系统，它包含在一个相对小的C库中。目前在很多嵌入式产品中使用了它，它占用资源非常的低，在嵌入式设备中，可能只需要几百K的内存就够了。它能够支持Windows/Linux/Unix/Android/IOS等等主流的操作系统，同时能够跟很多程序语言相结合，比如 Tcl、C#、PHP、Java等，还有ODBC接口，同样比起Mysql、PostgreSQL这两款开源的世界著名数据库管理系统来讲，它的处理速度比他们都快。
原创部分：
我项目中一共用到了三四个表，基本上大同小异，就挑出一个描述一下，垃圾代码如下
AccountInformationDatebase.java
package database.operate;
import java.util.ArrayList;
import java.util.List;
import object.AccountInfo;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import net.sqlcipher.database.SQLiteDatabase;
import net.sqlcipher.database.SQLiteOpenHelper;
public class AccountInformationDatabase {
static final String KEY_ROWID = "_id";
static final String KEY_APPNAME = "SOFTNAME";
static final String KEY_NUMBER = "NUMBER"; //账号
static final String KEY_PASSWORD = "PASSWORD"; //密码
static final String TAG = "AccountInformationDatabase";
static final String DATABASE_NAME = "InformationDatabase";
static final String DATABASE_TABLE = "AccountInformationTABLE";
static final int DATABASE_VERSION = 1;
static final String DATABASE_CREATE =
"create table if not exists FileInformationTABLE( _id integer primary key autoincrement, " +
"FILENAME text not null, fileSHA3 text not null, PASSWORD text not null);";
static final String DATABASE_AccountCREATE =
"create table if not exists AccountInformationTABLE( _id integer primary key autoincrement, " +
"NUMBER text not null, PASSWORD text not null, SOFTNAME text not null);";
static final String DATABASE_ClientCREATE =
"create table if not exists ClientInformationTABLE( _id integer primary key autoincrement, " +
"ClientNAME text not null, ClientIP text not null, ClientMAC text not null);";
static final String DATABASE_ShareCREATE =
"create table if not exists ShareInformationTABLE( _id integer primary key autoincrement, " +
"ShareFILENAME text not null, SharefileSHA3 text not null, SharePASSWORD text not null);";
static final String DATABASE_MasterPrivateCREATE =
"create table if not exists MasterPrivateTABLE( _id integer primary key autoincrement, " +
"PROPERTY text not null, PRIVATEKEY text not null);";
static final String DATABASE_MasterPublicCREATE =
"create table if not exists MasterPublicTABLE( _id integer primary key autoincrement, " +
"MASTERKEY text not null, PUBLICKEY text not null);";
static final String DATABASE_MinorPrivateCREATE =
"create table if not exists MinorPrivateTABLE( _id integer primary key autoincrement, " +
"PROPERTY text not null, PRIVATEKEY text not null);";
final Context context;
DatabaseHelper DBHelper;
SQLiteDatabase db;
public AccountInformationDatabase(Context cxt)
{
this.context = cxt;
DBHelper = new DatabaseHelper(context);
}
public static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
SQLiteDatabase.loadLibs(context);
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
try
{
db.execSQL(DATABASE_AccountCREATE); //add table
db.execSQL(DATABASE_ShareCREATE);
db.execSQL(DATABASE_CREATE); //add table
db.execSQL(DATABASE_ClientCREATE); //add table
db.execSQL(DATABASE_MinorPrivateCREATE);
db.execSQL(DATABASE_MasterPublicCREATE);
db.execSQL(DATABASE_MasterPrivateCREATE);
}
catch(SQLException e)
{
e.printStackTrace();
}
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
db.execSQL("DROP TABLE IF EXISTS AccountInformationTABLE");
onCreate(db);
}
}
//open the database
public AccountInformationDatabase open(String key) throws SQLException
{
db = DBHelper.getWritableDatabase(key);
return this;
}
//close the database
public void close()
{
DBHelper.close();
}
//insert a contact into the database
public long insertContact(String number, String password, String softname)
{
//查询插入是否存在
if(find(number,softname)==null){ //插入数据不存在
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NUMBER, number);
initialValues.put(KEY_PASSWORD, password);
initialValues.put(KEY_APPNAME, softname);
return db.insert(DATABASE_TABLE, null, initialValues);
}
else
return -1;
}
//delete a particular contact
public boolean deleteContact(String number,String softname)
{
if(find(number,softname)!=null){ //数据存在
return db.delete(DATABASE_TABLE, "NUMBER=? and SOFTNAME=?", new String[]{number,softname}) > 0;
}
else
return false;
}
public AccountInfo find(String number,String softname){ //精确查询
//如果只对数据进行读取，建议使用此方法
Cursor cursor = db.rawQuery("select * from AccountInformationTABLE where NUMBER=? and SOFTNAME=?", new String[]{number,softname});//得到游标
if(cursor.moveToFirst()){
String NUMBER = cursor.getString(cursor.getColumnIndex("NUMBER"));
String PASSWORD = cursor.getString(cursor.getColumnIndex("PASSWORD"));
String SOFTNAME=cursor.getString(cursor.getColumnIndex("SOFTNAME"));
AccountInfo person = new AccountInfo(NUMBER, PASSWORD, SOFTNAME);
return person;
}
else
return null; //查询失败，无相关数据
}
public List<AccountInfo> getScrollData(){ //返回全部数据
List<AccountInfo> AccountList = new ArrayList<AccountInfo>();
Cursor cursor = db.rawQuery("select * from AccountInformationTABLE where PASSWORD like?", new String[]{"%%"});//得到游标
while(cursor.moveToNext()){
String number = cursor.getString(cursor.getColumnIndex("NUMBER"));
String password = cursor.getString(cursor.getColumnIndex("PASSWORD"));
String softname = cursor.getString(cursor.getColumnIndex("SOFTNAME"));
AccountInfo person = new AccountInfo(number, password, softname);
AccountList.add(person);
}
cursor.close();
return AccountList;
}
public boolean updateContact(String number, String password, String softname)
{
if(find(number,softname)!= null){ //插入数据存在
ContentValues args = new ContentValues();
args.put(KEY_NUMBER, number);
args.put(KEY_PASSWORD, password);
args.put(KEY_APPNAME, softname);
return db.update(DATABASE_TABLE, args, KEY_NUMBER + " = ? and SOFTNAME = ?", new String[]{number,softname}) > 0;
}
else
return false;
}
}
做一个简单的调用，EditText录入文本存储到SQlite中。
Account = et1.getText().toString();
Password = et2.getText().toString();
AccountInformationDatabase account =new AccountInformationDatabase(SaftyBox_AddAccount.this);
account.open("ahjdabjk");//SQLite密钥
AccountCipher = Encryption.deal(Account,1,key);
PasswordCipher = Encryption.deal(Password,1,key);
//这里是用SMS4对文本加密过后在存到SQLite中的
account.insertContact(AccountCipher, PasswordCipher, Application);
Toast.makeText(getApplicationContext(), "添加成功！",Toast.LENGTH_SHORT).show();
account.close();
其他的表类似，不多做解释。如有问题，欢迎大佬指点。