Groovy example source code file (Utilities.java)

This example Groovy source code file (Utilities.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

invalid_java_identifiers, invalid_java_identifiers, set, string, string, stringbuffer, stringbuffer, util, utilities, utilities

The Groovy Utilities.java source code

/*
 * Copyright 2003-2007 the original author or authors.
 *
 * 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 org.codehaus.groovy.tools;

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

/**
 *  Various utility functions for use in the compiler.
 */

public abstract class Utilities
{
    private static final Set<String> INVALID_JAVA_IDENTIFIERS = new HashSet(Arrays.asList((
            "abstract assert boolean break byte case catch char class const continue default do double else enum " +
            "extends final finally float for goto if implements import instanceof int interface long native new " +
            "package private protected public short static strictfp super switch synchronized this throw throws " +
            "transient try void volatile while true false null").split(" ")));

   /**
    *  Returns a string made up of repetitions of the specified string.
    */

    public static String repeatString( String pattern, int repeats )
    {
        StringBuffer buffer = new StringBuffer( pattern.length() * repeats );
        for( int i = 0; i < repeats; i++ )
        {
            buffer.append( pattern );
        }

        return new String( buffer );
    }


   /**
    *  Returns the end-of-line marker.
    */

    public static String eol()
    {
        return eol;
    }

    /**
     * Tells if the given string is a valid Java identifier.
     */
    public static boolean isJavaIdentifier(String name) {
        if (name.length() == 0 || INVALID_JAVA_IDENTIFIERS.contains(name)) return false;
        char[] chars = name.toCharArray();
        if (!Character.isJavaIdentifierStart(chars[0])) return false;
        for (int i = 1; i < chars.length; i++ ) {
            if (!Character.isJavaIdentifierPart(chars[i])) return false;
        }
        return true;
    }    
    
    private static String eol = System.getProperty( "line.separator", "\n" );

}