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Android example source code file (SQLiteClosable.java)

This example Android source code file (SQLiteClosable.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" TM.

Java - Android tags/keywords

android, cursorwindow, database, illegalstateexception, object, sqliteclosable, sqlitedatabase, sqliteprogram, sqlitequery, sqlitestatement, stringbuilder

The SQLiteClosable.java Android example source code

/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.database.sqlite;

import android.database.CursorWindow;

/**
 * An object created from a SQLiteDatabase that can be closed.
 */
public abstract class SQLiteClosable {
    private int mReferenceCount = 1;
    private Object mLock = new Object();

    protected abstract void onAllReferencesReleased();
    protected void onAllReferencesReleasedFromContainer() {}

    public void acquireReference() {
        synchronized(mLock) {
            if (mReferenceCount <= 0) {
                throw new IllegalStateException(
                        "attempt to re-open an already-closed object: " + getObjInfo());
            }
            mReferenceCount++;
        }
    }

    public void releaseReference() {
        synchronized(mLock) {
            mReferenceCount--;
            if (mReferenceCount == 0) {
                onAllReferencesReleased();
            }
        }
    }

    public void releaseReferenceFromContainer() {
        synchronized(mLock) {
            mReferenceCount--;
            if (mReferenceCount == 0) {
                onAllReferencesReleasedFromContainer();
            }
        }
    }

    private String getObjInfo() {
        StringBuilder buff = new StringBuilder();
        buff.append(this.getClass().getName());
        buff.append(" (");
        if (this instanceof SQLiteDatabase) {
            buff.append("database = ");
            buff.append(((SQLiteDatabase)this).getPath());
        } else if (this instanceof SQLiteProgram || this instanceof SQLiteStatement ||
                this instanceof SQLiteQuery) {
            buff.append("mSql = ");
            buff.append(((SQLiteProgram)this).mSql);
        } else if (this instanceof CursorWindow) {
            buff.append("mStartPos = ");
            buff.append(((CursorWindow)this).getStartPosition());
        }
        buff.append(") ");
        return buff.toString();
    }
}

Other Android examples (source code examples)

Here is a short list of links related to this Android SQLiteClosable.java source code file:

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