core/java/android/net/SSLSessionCache.java

/*
 * Copyright (C) 2010 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.net;

import android.content.Context;
import android.util.Log;

import com.android.org.conscrypt.FileClientSessionCache;
import com.android.org.conscrypt.SSLClientSessionCache;

import java.io.File;
import java.io.IOException;

/**
 * File-based cache of established SSL sessions.  When re-establishing a
 * connection to the same server, using an SSL session cache can save some time,
 * power, and bandwidth by skipping directly to an encrypted stream.
 * This is a persistent cache which can span executions of the application.
 *
 * @see SSLCertificateSocketFactory
 */
public final class SSLSessionCache {
    private static final String TAG = "SSLSessionCache";
    /* package */ final SSLClientSessionCache mSessionCache;

    /**
     * Create a session cache using the specified directory.
     * Individual session entries will be files within the directory.
     * Multiple instances for the same directory share data internally.
     *
     * @param dir to store session files in (created if necessary)
     * @throws IOException if the cache can't be opened
     */
    public SSLSessionCache(File dir) throws IOException {
        mSessionCache = FileClientSessionCache.usingDirectory(dir);
    }

    /**
     * Create a session cache at the default location for this app.
     * Multiple instances share data internally.
     *
     * @param context for the application
     */
    public SSLSessionCache(Context context) {
        File dir = context.getDir("sslcache", Context.MODE_PRIVATE);
        SSLClientSessionCache cache = null;
        try {
            cache = FileClientSessionCache.usingDirectory(dir);
        } catch (IOException e) {
            Log.w(TAG, "Unable to create SSL session cache in " + dir, e);
        }
        mSessionCache = cache;
    }
}