ResourceBundle String manager
/*
* Copyright (C) 2003 Colin Bell
* colbell@users.sourceforge.net
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
import java.text.MessageFormat;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;
import java.net.URLClassLoader;
import java.net.URL;
/**
* This class defines i18nized strings. These strings are stored in a file
* with a base name I18NStrings.properties in each package directory.
*
* @author <A HREF="mailto:colbell@users.sourceforge.net">Colin Bell</A>
*/
public class StringManager
{
/** Contains the localised strings. */
private ResourceBundle _rsrcBundle;
private String _bundleBaseName;
private URL[] _bundleLoaderUrLs = new URL[0];
/** a flag to indicate whether or not to throw exception for missing resource string */
private static boolean _testMode = false;
/**
* Ctor specifying the package name. Attempt to load a resource bundle
* from the package directory.
*
* @param packageName Name of package
* @param classLoader Class loader to use
*/
StringManager(String packageName, ClassLoader loader)
{
super();
_bundleBaseName = packageName + ".I18NStrings";
_rsrcBundle = ResourceBundle.getBundle(_bundleBaseName, Locale.getDefault(), loader);
if(loader instanceof URLClassLoader)
{
_bundleLoaderUrLs = ((URLClassLoader) loader).getURLs();
}
}
/**
* Retrieve the localized string for the passed key. If it isn't found
* an error message is returned instead.
*
* @param key Key to retrieve string for.
*
* @return Localized string or error message.
*
* @throws IllegalArgumentException
* Thrown if <TT>null</TT> <TT>key</TT> passed.
*/
public String getString(String key)
{
if (key == null)
{
throw new IllegalArgumentException("key == null");
}
try
{
return _rsrcBundle.getString(key);
}
catch (MissingResourceException ex)
{
StringBuilder sb = new StringBuilder();
sb.append("No resource string found for key '" + key + "' in bundle " + _bundleBaseName + "\n\n");
if(0 < _bundleLoaderUrLs.length)
{
sb.append("The following classpath entries are available to the bundle loader:\n");
for (int i = 0; i < _bundleLoaderUrLs.length; i++)
{
sb.append(_bundleLoaderUrLs[i]).append("\n");
}
}
if (_testMode) {
throw new IllegalStateException(sb.toString());
}
return "No resource found for key " + key;
}
}
/**
* Retrieve the localized string for the passed key and format it with the
* passed arguments.
*
* @param key Key to retrieve string for.
* @param args Any string arguments that should be used as values to
* parameters found in the localized string.
*
* @return Localized string or error message.
*
* @throws IllegalArgumentException
* Thrown if <TT>null</TT> <TT>key</TT> passed.
*/
public String getString(String key, String[] args)
{
return getString(key, (Object[])args);
}
/**
* Retrieve the localized string for the passed key and format it with the
* passed arguments.
*
* @param key Key to retrieve string for.
* @param args Any string arguments that should be used as values to
* parameters found in the localized string.
*
* @return Localized string or error message.
*
* @throws IllegalArgumentException
* Thrown if <TT>null</TT> <TT>key</TT> passed.
*/
public String getString(String key, Object... args)
{
if (key == null)
{
throw new IllegalArgumentException("key == null");
}
if (args == null)
{
args = new Object[0];
}
final String str = getString(key);
try
{
return MessageFormat.format(str, args);
}
catch (IllegalArgumentException ex)
{
String msg = "Error formatting i18 string. Key is '" + key + "'";
return msg + ": " + ex.toString();
}
}
/**
* Allows the caller to enable/disable test mode which results in an exception being thrown for no
* resource string defined.
*
* @param enabled
*/
public static void setTestMode(boolean enabled) {
_testMode = enabled;
}
}
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