android SQLiteDatabase源码解析

源于包android.database.sqlite.SQLiteDatabase

 首先看一下继承和实现了那些基类和接口

 SQLiteDatabase extends SQLiteClosable  implements Closeable Closeable extends AutoCloseable
 interface   AutoCloseable ／／java. langvoid close() throws Exception;
Defines an interface for classes that can (or need to) be closed once they * are not used any longer. Calling the {@code close} method releases resources * that the object holds.
一旦不用回收释放资源,关闭资源
interface Closeable extends AutoCloseable   //java.io
void close() throws IOException;
Closeable是可以关闭的数据源或目标。调用 close 方法可释放对象保存的资源（如打开文件）
关闭此流并释放与此流关联的所有系统资源。如果已经关闭该流，则调用此方法无效。 
abstract class SQLiteClosable implements Closeable //  抽象类
abstract void onAllReferencesReleased();／／
void onAllReferencesReleasedFromContainer()
void acquireReference()
void releaseReference()
void releaseReferenceFromContainer()
public void close() {    releaseReference();／／实现Closeable的方法}

final class SQLiteDatabase 
public static SQLiteDatabase openDatabase(String path, CursorFactory factory, int flags) {    return openDatabase(path, factory, flags, null);}
public static SQLiteDatabase openDatabase(String path, CursorFactory factory, int flags,        DatabaseErrorHandler errorHandler) {／／路径    cuesor构造器，传null使用默认构造器     SQLiteDatabase db = new SQLiteDatabase(path, flags, factory, errorHandler);    db.open();    return db;}
public static boolean deleteDatabase(File file) ／／删除数据库
public void reopenReadWrite()
public Cursor query(boolean distinct, String table, String[] columns,        String selection, String[] selectionArgs, String groupBy,        String having, String orderBy, String limit) {    return queryWithFactory(null, distinct, table, columns, selection, selectionArgs,            groupBy, having, orderBy, limit, null);}

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