001    /*
002     *  This file is part of the Jikes RVM project (http://jikesrvm.org).
003     *
004     *  This file is licensed to You under the Eclipse Public License (EPL);
005     *  You may not use this file except in compliance with the License. You
006     *  may obtain a copy of the License at
007     *
008     *      http://www.opensource.org/licenses/eclipse-1.0.php
009     *
010     *  See the COPYRIGHT.txt file distributed with this work for information
011     *  regarding copyright ownership.
012     */
013    package org.vmutil.options;
014    
015    import org.vmmagic.pragma.Uninterruptible;
016    
017    /**
018     * An option that has a simple string value.
019     */
020    public class StringOption extends Option {
021      // values
022      protected String defaultValue;
023      protected String value;
024    
025      /**
026       * Create a new string option.
027       *
028       * @param set The option set this option belongs to.
029       * @param name The space separated name for the option.
030       * @param desc The purpose of the option
031       * @param defaultValue The default value of the option.
032       */
033      protected StringOption(OptionSet set, String name, String desc, String defaultValue) {
034        super(set, STRING_OPTION, name, desc);
035        this.value = this.defaultValue = defaultValue;
036      }
037    
038      /**
039       * Read the current value of the option.
040       *
041       * @return The option value.
042       */
043      @Uninterruptible
044      public String getValue() {
045        return this.value;
046      }
047    
048      /**
049       * Read the default value of the option
050       *
051       * @return The default value.
052       */
053      @Uninterruptible
054      public String getDefaultValue() {
055        return this.defaultValue;
056      }
057    
058      /**
059       * Update the value of the option, echoing the change if the echoOptions
060       * option is set. This method also calls the validate method to allow
061       * subclasses to perform any required validation.
062       *
063       * @param value The new value for the option.
064       */
065      public void setValue(String value) {
066        this.value = value;
067        validate();
068        set.logChange(this);
069      }
070    
071      /**
072       * Modify the default value of the option.
073       *
074       * @param value The new default value for the option.
075       */
076      public void setDefaultValue(String value) {
077        this.value = this.defaultValue = value;
078      }
079    }