Java Thread Lock getAllMessages()

Description

get All Messages

License

Open Source License

Return

the map of all available messages for the current locale

Declaration

public static Map<String, String> getAllMessages() 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;

import java.util.Locale;
import java.util.Map;
import java.util.ResourceBundle;
import java.util.Set;

import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

public class Main {
    /**/*from   www. ja v  a  2  s .c  o  m*/
     * Thread-local containing the general Locale for the current thread
     */
    private static ThreadLocal<Locale> threadLocale = new ThreadLocal<Locale>();
    /**
     * List of registered bundles
     */
    private static Set<String> resouceBundleBaseNames = new HashSet<String>();
    /**
     * Map of loaded bundles by Locale
     */
    private static Map<Locale, Set<String>> loadedResourceBundles = new HashMap<Locale, Set<String>>();
    /**
     * Map of cached messaged by Locale
     */
    private static Map<Locale, Map<String, String>> cachedMessages = new HashMap<Locale, Map<String, String>>();
    /**
     * Lock objects
     */
    private static ReadWriteLock lock = new ReentrantReadWriteLock();
    private static Lock readLock = lock.readLock();
    private static Lock writeLock = lock.writeLock();

    /**
     * @return the map of all available messages for the current locale
     */
    public static Map<String, String> getAllMessages() {
        return getLocaleProperties(getLocale());
    }

    /**
     * @return the map of all available messages for the specified locale
     */
    public static Map<String, String> getAllMessages(Locale locale) {
        return getLocaleProperties(locale);
    }

    /**
     * Get the messages for a locale.
     * <p>
     * Will use cache where available otherwise will load into cache from bundles.
     *
     * @param locale    the locale
     * @return          message map
     */
    private static Map<String, String> getLocaleProperties(Locale locale) {
        Set<String> loadedBundles = null;
        Map<String, String> props = null;
        int loadedBundleCount = 0;
        try {
            readLock.lock();
            loadedBundles = loadedResourceBundles.get(locale);
            props = cachedMessages.get(locale);
            loadedBundleCount = resouceBundleBaseNames.size();
        } finally {
            readLock.unlock();
        }

        if (loadedBundles == null) {
            try {
                writeLock.lock();
                loadedBundles = new HashSet<String>();
                loadedResourceBundles.put(locale, loadedBundles);
            } finally {
                writeLock.unlock();
            }
        }

        if (props == null) {
            try {
                writeLock.lock();
                props = new HashMap<String, String>();
                cachedMessages.put(locale, props);
            } finally {
                writeLock.unlock();
            }
        }

        if (loadedBundles.size() != loadedBundleCount) {
            try {
                writeLock.lock();
                for (String resourceBundleBaseName : resouceBundleBaseNames) {
                    if (loadedBundles.contains(resourceBundleBaseName) == false) {
                        ResourceBundle resourcebundle = ResourceBundle.getBundle(resourceBundleBaseName, locale);
                        Enumeration<String> enumKeys = resourcebundle.getKeys();
                        while (enumKeys.hasMoreElements() == true) {
                            String key = enumKeys.nextElement();
                            props.put(key, resourcebundle.getString(key));
                        }
                        loadedBundles.add(resourceBundleBaseName);
                    }
                }
            } finally {
                writeLock.unlock();
            }
        }

        return props;
    }

    /**
     * Get the general local for the current thread, will revert to the default locale if none
     * specified for this thread.
     *
     * @return  the general locale
     */
    public static Locale getLocale() {
        Locale locale = threadLocale.get();
        if (locale == null) {
            // Get the default locale
            locale = Locale.getDefault();
        }
        return locale;
    }
}

Related

1. canCreateNewThread()
2. createConcurrentStack()
3. downgradeWriteLock(final ReadWriteLock lock)
4. fillReadWriteLocks(List readLocks, List writeLocks, int curSize, int size)
5. getGradingReadLock()
6. getInstance()
7. getLocaleProperties(Locale locale)
8. getPropLock(String s)