/*
* 12/12/2008
*
* TokenMakerFactory.java - A factory for TokenMakers.
*
* This library is distributed under a modified BSD license. See the included
* RSyntaxTextArea.License.txt file for details.
*/
package org.fife.ui.rsyntaxtextarea;
import java.util.Set;
import org.fife.ui.rsyntaxtextarea.modes.PlainTextTokenMaker;
/**
* A factory that maps syntax styles to {@link TokenMaker}s capable of splitting
* text into tokens for those syntax styles.
*
* @author Robert Futrell
* @version 1.0
*/
public abstract class TokenMakerFactory {
/**
* If this system property is set, a custom <code>TokenMakerFactory</code>
* of the specified class will be used as the default token maker factory.
*/
public static final String PROPERTY_DEFAULT_TOKEN_MAKER_FACTORY =
"TokenMakerFactory";
/**
* The singleton default <code>TokenMakerFactory</code> instance.
*/
private static TokenMakerFactory DEFAULT_INSTANCE;
/**
* Returns the default <code>TokenMakerFactory</code> instance. This is
* the factory used by all {@link RSyntaxDocument}s by default.
*
* @return The factory.
* @see #setDefaultInstance(TokenMakerFactory)
*/
public static synchronized TokenMakerFactory getDefaultInstance() {
if (DEFAULT_INSTANCE==null) {
String clazz = null;
try {
clazz= System.getProperty(PROPERTY_DEFAULT_TOKEN_MAKER_FACTORY);
} catch (java.security.AccessControlException ace) {
clazz = null; // We're in an applet; take default.
}
if (clazz==null) {
clazz = "org.fife.ui.rsyntaxtextarea.DefaultTokenMakerFactory";
}
try {
DEFAULT_INSTANCE = (TokenMakerFactory)Class.forName(clazz).
newInstance();
} catch (RuntimeException re) { // FindBugs
throw re;
} catch (Exception e) {
e.printStackTrace();
throw new InternalError("Cannot find TokenMakerFactory: " +
clazz);
}
}
return DEFAULT_INSTANCE;
}
/**
* Returns a {@link TokenMaker} for the specified key.
*
* @param key The key.
* @return The corresponding <code>TokenMaker</code>, or
* {@link PlainTextTokenMaker} if none matches the specified key.
*/
public final TokenMaker getTokenMaker(String key) {
TokenMaker tm = getTokenMakerImpl(key);
if (tm==null) {
tm = new PlainTextTokenMaker();
}
return tm;
}
/**
* Returns a {@link TokenMaker} for the specified key.
*
* @param key The key.
* @return The corresponding <code>TokenMaker</code>, or <code>null</code>
* if none matches the specified key.
*/
protected abstract TokenMaker getTokenMakerImpl(String key);
/**
* Returns the set of keys that this factory maps to token makers.
*
* @return The set of keys.
*/
public abstract Set keySet();
/**
* Sets the default <code>TokenMakerFactory</code> instance. This is
* the factory used by all future {@link RSyntaxDocument}s by default.
* <code>RSyntaxDocument</code>s that have already been created are not
* affected.
*
* @param tmf The factory.
* @throws IllegalArgumentException If <code>tmf</code> is
* <code>null</code>.
* @see #getDefaultInstance()
*/
public static synchronized void setDefaultInstance(TokenMakerFactory tmf) {
if (tmf==null) {
throw new IllegalArgumentException("tmf cannot be null");
}
DEFAULT_INSTANCE = tmf;
}
}