luni/src/test/java/libcore/java/util/prefs/PreferencesTest.java

/*
 * Copyright (C) 2011 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 libcore.java.util.prefs;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.prefs.FileSystemPreferences;
import java.util.prefs.Preferences;
import java.util.prefs.PreferencesFactory;
import junit.framework.TestCase;
import libcore.io.IoUtils;

public final class PreferencesTest extends TestCase {

    /**
     * A preferences factory rooted at a given path.
     */
    public static final class TestPreferencesFactory implements PreferencesFactory {
        private final Preferences userPrefs;
        private final Preferences systemPrefs;

        private final File userLockFile;
        private final File systemLockFile;

        public TestPreferencesFactory(String root) throws IOException {
            userLockFile = new File(root, "user.lock");
            systemLockFile = new File(root, "system.lock");
            assertTrue(userLockFile.createNewFile());
            assertTrue(systemLockFile.createNewFile());
            userPrefs = new FileSystemPreferences(root + "/user", userLockFile, true);
            systemPrefs = new FileSystemPreferences(root + "/system", systemLockFile, false);        }

        public Preferences userRoot() {
            return userPrefs;
        }

        public Preferences systemRoot() {
            return systemPrefs;
        }
    }

    private PreferencesFactory defaultFactory;
    private File temporaryDirectory;

    @Override
    public void setUp() throws Exception {
        temporaryDirectory = IoUtils.createTemporaryDirectory("PreferencesTest");
        defaultFactory = Preferences.setPreferencesFactory(
                new TestPreferencesFactory(temporaryDirectory.getAbsolutePath()));
    }

    @Override
    public void tearDown() throws Exception {
        Preferences.setPreferencesFactory(defaultFactory);
    }

    /**
     * The preferences API is designed to be hostile towards files that exist
     * where it wants to store its XML data. http://b/3431233
     */
    public void testPreferencesClobbersExistingFiles() throws Exception {
        final File userPrefsDir = new File(temporaryDirectory + "/user");
        assertTrue(userPrefsDir.mkdir());
        final File userPrefs = new File(userPrefsDir, "prefs.xml");
        assertTrue(userPrefs.createNewFile());
        FileWriter writer = new FileWriter(userPrefs);
        writer.write("lamb");
        writer.close();
        userPrefs.setReadable(false);
        userPrefs.setWritable(false);
        long oldLength = userPrefs.length();

        Preferences userPreferences = Preferences.userRoot();
        userPreferences.sync();
        userPreferences.put("a", "lion");
        userPreferences.flush();
        assertTrue("Expected to exist " + userPrefs, userPrefs.exists());
        assertTrue("Expected file to be clobbered", oldLength != userPrefs.length());
    }

    public void testHtmlEncoding() throws Exception {
        Preferences parent = Preferences.userNodeForPackage(this.getClass());
        Preferences p = parent.node("testHtmlEncoding");
        p.put("key", "a<>&'\"\\b");
        p.flush();

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        p.exportNode(baos);

        String s = new String(baos.toByteArray(), "UTF-8");
        assertTrue(s, s.contains("value=\"a&lt;&gt;&amp;'&quot;\\b\""));
    }
}