src/java/org/apache/jcs/config/OptionConverter.java - commons-jcs - Git at Google

 package org.apache.jcs.config;


 /*
  * Copyright 2001-2004 The Apache Software Foundation.
  *
  * 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.
  */


 import java.util.Properties;

 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;

 /**
  * This class is based on the log4j class
  * org.apache.log4j.helpers.OptionConverter that was made by Ceki
  * G&uuml;lc&uuml; Simon Kitching; Avy Sharell (sharell@online.fr) Anders
  * Kristensen Matthieu Verbert (mve@zurich.ibm.com) A convenience class to
  * convert property values to specific types.
  *
  */
 public class OptionConverter
 {
     private final static Log log =
         LogFactory.getLog( OptionConverter.class );

     static String DELIM_START = "${";
     static char DELIM_STOP = '}';
     static int DELIM_START_LEN = 2;
     static int DELIM_STOP_LEN = 1;

     static StringBuffer sbuf = new StringBuffer();

     /** OptionConverter is a static class. */
     private OptionConverter() { }


     /** Description of the Method */
     public static String[] concatanateArrays( String[] l, String[] r )
     {
         int len = l.length + r.length;
         String[] a = new String[len];

         System.arraycopy( l, 0, a, 0, l.length );
         System.arraycopy( r, 0, a, l.length, r.length );

         return a;
     }


     /** Description of the Method */
     public static String convertSpecialChars( String s )
     {
         char c;
         int len = s.length();
         StringBuffer sbuf = new StringBuffer( len );

         int i = 0;
         while ( i < len )
         {
             c = s.charAt( i++ );
             if ( c == '\\' )
             {
                 c = s.charAt( i++ );
                 if ( c == 'n' )
                 {
                     c = '\n';
                 }
                 else if ( c == 'r' )
                 {
                     c = '\r';
                 }
                 else if ( c == 't' )
                 {
                     c = '\t';
                 }
                 else if ( c == 'f' )
                 {
                     c = '\f';
                 }
                 else if ( c == '\b' )
                 {
                     c = '\b';
                 }
                 else if ( c == '\"' )
                 {
                     c = '\"';
                 }
                 else if ( c == '\'' )
                 {
                     c = '\'';
                 }
                 else if ( c == '\\' )
                 {
                     c = '\\';
                 }
             }
             sbuf.append( c );
         }
         return sbuf.toString();
     }


     /**
      * Very similar to <code>System.getProperty</code> except that the {@link
      * SecurityException} is hidden.
      *
      * @param key The key to search for.
      * @param def The default value to return.
      * @return the string value of the system property, or the default value if
      *      there is no property with that key.
      * @since 1.1
      */

     public static String getSystemProperty( String key, String def )
     {
         try
         {
             return System.getProperty( key, def );
         }
         catch ( Throwable e )
         {
             // MS-Java throws com.ms.security.SecurityExceptionEx
             log.debug( "Was not allowed to read system property \"" + key + "\"." );
             return def;
         }
     }


     /** Description of the Method */
     public static Object instantiateByKey( Properties props, String key, Class superClass,
                                            Object defaultValue )
     {

         // Get the value of the property in string form
         String className = findAndSubst( key, props );
         if ( className == null )
         {
             log.warn( "Could not find value for key " + key );
             return defaultValue;
         }
         // Trim className to avoid trailing spaces that cause problems.
         return OptionConverter.instantiateByClassName( className.trim(), superClass,
             defaultValue );
     }


     /**
      * If <code>value</code> is "true", then <code>true</code> is returned. If
      * <code>value</code> is "false", then <code>true</code> is returned.
      * Otherwise, <code>default</code> is returned. <p>
      *
      * Case of value is unimportant.
      */

     public static boolean toBoolean( String value, boolean dEfault )
     {
         if ( value == null )
         {
             return dEfault;
         }
         String trimmedVal = value.trim();
         if ( "true".equalsIgnoreCase( trimmedVal ) )
         {
             return true;
         }
         if ( "false".equalsIgnoreCase( trimmedVal ) )
         {
             return false;
         }
         return dEfault;
     }


     /** Description of the Method */
     public static int toInt( String value, int dEfault )
     {
         if ( value != null )
         {
             String s = value.trim();
             try
             {
                 return Integer.valueOf( s ).intValue();
             }
             catch ( NumberFormatException e )
             {
                 log.error( "[" + s + "] is not in proper int form." );
                 e.printStackTrace();
             }
         }
         return dEfault;
     }


     /** Description of the Method */
     public static long toFileSize( String value, long dEfault )
     {
         if ( value == null )
         {
             return dEfault;
         }

         String s = value.trim().toUpperCase();
         long multiplier = 1;
         int index;

         if ( ( index = s.indexOf( "KB" ) ) != -1 )
         {
             multiplier = 1024;
             s = s.substring( 0, index );
         }
         else if ( ( index = s.indexOf( "MB" ) ) != -1 )
         {
             multiplier = 1024 * 1024;
             s = s.substring( 0, index );
         }
         else if ( ( index = s.indexOf( "GB" ) ) != -1 )
         {
             multiplier = 1024 * 1024 * 1024;
             s = s.substring( 0, index );
         }
         if ( s != null )
         {
             try
             {
                 return Long.valueOf( s ).longValue() * multiplier;
             }
             catch ( NumberFormatException e )
             {
                 log.error( "[" + s + "] is not in proper int form" );
                 log.error( "[" + value + "] not in expected format", e );
             }
         }
         return dEfault;
     }


     /**
      * Find the value corresponding to <code>key</code> in <code>props</code>.
      * Then perform variable substitution on the found value.
      */

     public static String findAndSubst( String key, Properties props )
     {
         String value = props.getProperty( key );
         if ( value == null )
         {
             return null;
         }

         try
         {
             return substVars( value, props );
         }
         catch ( IllegalArgumentException e )
         {
             log.error( "Bad option value [" + value + "]", e );
             return value;
         }
     }


     /**
      * Instantiate an object given a class name. Check that the <code>className</code>
      * is a subclass of <code>superClass</code>. If that test fails or the
      * object could not be instantiated, then <code>defaultValue</code> is
      * returned.
      *
      * @param className The fully qualified class name of the object to
      *      instantiate.
      * @param superClass The class to which the new object should belong.
      * @param defaultValue The object to return in case of non-fulfillment
      */

     public static Object instantiateByClassName( String className, Class superClass,
                                                  Object defaultValue )
     {
         if ( className != null )
         {
             try
             {
                 Class classObj = Class.forName( className );
                 if ( !superClass.isAssignableFrom( classObj ) )
                 {
                     log.error( "A \"" + className + "\" object is not assignable to a \"" +
                         superClass.getName() + "\" variable." );
                     return defaultValue;
                 }
                 return classObj.newInstance();
             }
             catch ( Exception e )
             {
                 log.error( "Could not instantiate class [" + className + "]", e );
             }
         }
         return defaultValue;
     }

     /**
      * Perform variable substitution in string <code>val</code> from the values
      * of keys found in the system propeties. <p>
      *
      * The variable substitution delimeters are <b>${</b> and <b>}</b> . <p>
      *
      * For example, if the System properties contains "key=value", then the call
      * <pre>
      *String s = OptionConverter.substituteVars("Value of key is ${key}.");
      *</pre> will set the variable <code>s</code> to "Value of key is value.".
      * <p>
      *
      * If no value could be found for the specified key, then the <code>props</code>
      * parameter is searched, if the value could not be found there, then
      * substitution defaults to the empty string. <p>
      *
      * For example, if system propeties contains no value for the key
      * "inexistentKey", then the call <pre>
      *String s = OptionConverter.subsVars("Value of inexistentKey is [${inexistentKey}]");
      *</pre> will set <code>s</code> to "Value of inexistentKey is []" <p>
      *
      * An {@link java.lang.IllegalArgumentException} is thrown if <code>val</code>
      * contains a start delimeter "${" which is not balanced by a stop delimeter
      * "}". </p> <p>
      *
      * <b>Author</b> Avy Sharell</a> </p>
      *
      * @param val The string on which variable substitution is performed.
      * @throws IllegalArgumentException if <code>val</code> is malformed.
      */

     public static String substVars( String val, Properties props )
         throws
         IllegalArgumentException
     {
         sbuf.setLength( 0 );

         int i = 0;
         int j;
         int k;

         while ( true )
         {
             j = val.indexOf( DELIM_START, i );
             if ( j == -1 )
             {
                 if ( i == 0 )
                 {
                     return val;
                 }
 	            sbuf.append( val.substring( i, val.length() ) );
 	            return sbuf.toString();
             }
             sbuf.append( val.substring( i, j ) );
             k = val.indexOf( DELIM_STOP, j );
             if ( k == -1 )
             {
                 throw new IllegalArgumentException( '"' + val +
                     "\" has no closing brace. Opening brace at position " + j
                      + '.' );
             }
             j += DELIM_START_LEN;
             String key = val.substring( j, k );
             // first try in System properties
             String replacement = getSystemProperty( key, null );
             // then try props parameter
             if ( replacement == null && props != null )
             {
                 replacement = props.getProperty( key );
             }

             if ( replacement != null )
             {
                 sbuf.append( replacement );
             }
             i = k + DELIM_STOP_LEN;
         }
     }

 }
 // end class
	package org.apache.jcs.config;


	/*
	* Copyright 2001-2004 The Apache Software Foundation.
	*
	* 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.
	*/


	import java.util.Properties;

	import org.apache.commons.logging.Log;
	import org.apache.commons.logging.LogFactory;

	/**
	* This class is based on the log4j class
	* org.apache.log4j.helpers.OptionConverter that was made by Ceki
	* Gülcü Simon Kitching; Avy Sharell (sharell@online.fr) Anders
	* Kristensen Matthieu Verbert (mve@zurich.ibm.com) A convenience class to
	* convert property values to specific types.
	*
	*/
	public class OptionConverter
	{
	private final static Log log =
	LogFactory.getLog( OptionConverter.class );

	static String DELIM_START = "${";
	static char DELIM_STOP = '}';
	static int DELIM_START_LEN = 2;
	static int DELIM_STOP_LEN = 1;

	static StringBuffer sbuf = new StringBuffer();

	/** OptionConverter is a static class. */
	private OptionConverter() { }


	/** Description of the Method */
	public static String[] concatanateArrays( String[] l, String[] r )
	{
	int len = l.length + r.length;
	String[] a = new String[len];

	System.arraycopy( l, 0, a, 0, l.length );
	System.arraycopy( r, 0, a, l.length, r.length );

	return a;
	}


	/** Description of the Method */
	public static String convertSpecialChars( String s )
	{
	char c;
	int len = s.length();
	StringBuffer sbuf = new StringBuffer( len );

	int i = 0;
	while ( i < len )
	{
	c = s.charAt( i++ );
	if ( c == '\\' )
	{
	c = s.charAt( i++ );
	if ( c == 'n' )
	{
	c = '\n';
	}
	else if ( c == 'r' )
	{
	c = '\r';
	}
	else if ( c == 't' )
	{
	c = '\t';
	}
	else if ( c == 'f' )
	{
	c = '\f';
	}
	else if ( c == '\b' )
	{
	c = '\b';
	}
	else if ( c == '\"' )
	{
	c = '\"';
	}
	else if ( c == '\'' )
	{
	c = '\'';
	}
	else if ( c == '\\' )
	{
	c = '\\';
	}
	}
	sbuf.append( c );
	}
	return sbuf.toString();
	}


	/**
	* Very similar to <code>System.getProperty</code> except that the {@link
	* SecurityException} is hidden.
	*
	* @param key The key to search for.
	* @param def The default value to return.
	* @return the string value of the system property, or the default value if
	* there is no property with that key.
	* @since 1.1
	*/

	public static String getSystemProperty( String key, String def )
	{
	try
	{
	return System.getProperty( key, def );
	}
	catch ( Throwable e )
	{
	// MS-Java throws com.ms.security.SecurityExceptionEx
	log.debug( "Was not allowed to read system property \"" + key + "\"." );
	return def;
	}
	}


	/** Description of the Method */
	public static Object instantiateByKey( Properties props, String key, Class superClass,
	Object defaultValue )
	{

	// Get the value of the property in string form
	String className = findAndSubst( key, props );
	if ( className == null )
	{
	log.warn( "Could not find value for key " + key );
	return defaultValue;
	}
	// Trim className to avoid trailing spaces that cause problems.
	return OptionConverter.instantiateByClassName( className.trim(), superClass,
	defaultValue );
	}


	/**
	* If <code>value</code> is "true", then <code>true</code> is returned. If
	* <code>value</code> is "false", then <code>true</code> is returned.
	* Otherwise, <code>default</code> is returned. <p>
	*
	* Case of value is unimportant.
	*/

	public static boolean toBoolean( String value, boolean dEfault )
	{
	if ( value == null )
	{
	return dEfault;
	}
	String trimmedVal = value.trim();
	if ( "true".equalsIgnoreCase( trimmedVal ) )
	{
	return true;
	}
	if ( "false".equalsIgnoreCase( trimmedVal ) )
	{
	return false;
	}
	return dEfault;
	}


	/** Description of the Method */
	public static int toInt( String value, int dEfault )
	{
	if ( value != null )
	{
	String s = value.trim();
	try
	{
	return Integer.valueOf( s ).intValue();
	}
	catch ( NumberFormatException e )
	{
	log.error( "[" + s + "] is not in proper int form." );
	e.printStackTrace();
	}
	}
	return dEfault;
	}


	/** Description of the Method */
	public static long toFileSize( String value, long dEfault )
	{
	if ( value == null )
	{
	return dEfault;
	}

	String s = value.trim().toUpperCase();
	long multiplier = 1;
	int index;

	if ( ( index = s.indexOf( "KB" ) ) != -1 )
	{
	multiplier = 1024;
	s = s.substring( 0, index );
	}
	else if ( ( index = s.indexOf( "MB" ) ) != -1 )
	{
	multiplier = 1024 * 1024;
	s = s.substring( 0, index );
	}
	else if ( ( index = s.indexOf( "GB" ) ) != -1 )
	{
	multiplier = 1024 * 1024 * 1024;
	s = s.substring( 0, index );
	}
	if ( s != null )
	{
	try
	{
	return Long.valueOf( s ).longValue() * multiplier;
	}
	catch ( NumberFormatException e )
	{
	log.error( "[" + s + "] is not in proper int form" );
	log.error( "[" + value + "] not in expected format", e );
	}
	}
	return dEfault;
	}


	/**
	* Find the value corresponding to <code>key</code> in <code>props</code>.
	* Then perform variable substitution on the found value.
	*/

	public static String findAndSubst( String key, Properties props )
	{
	String value = props.getProperty( key );
	if ( value == null )
	{
	return null;
	}

	try
	{
	return substVars( value, props );
	}
	catch ( IllegalArgumentException e )
	{
	log.error( "Bad option value [" + value + "]", e );
	return value;
	}
	}


	/**
	* Instantiate an object given a class name. Check that the <code>className</code>
	* is a subclass of <code>superClass</code>. If that test fails or the
	* object could not be instantiated, then <code>defaultValue</code> is
	* returned.
	*
	* @param className The fully qualified class name of the object to
	* instantiate.
	* @param superClass The class to which the new object should belong.
	* @param defaultValue The object to return in case of non-fulfillment
	*/

	public static Object instantiateByClassName( String className, Class superClass,
	Object defaultValue )
	{
	if ( className != null )
	{
	try
	{
	Class classObj = Class.forName( className );
	if ( !superClass.isAssignableFrom( classObj ) )
	{
	log.error( "A \"" + className + "\" object is not assignable to a \"" +
	superClass.getName() + "\" variable." );
	return defaultValue;
	}
	return classObj.newInstance();
	}
	catch ( Exception e )
	{
	log.error( "Could not instantiate class [" + className + "]", e );
	}
	}
	return defaultValue;
	}

	/**
	* Perform variable substitution in string <code>val</code> from the values
	* of keys found in the system propeties. <p>
	*
	* The variable substitution delimeters are <b>${</b> and <b>}</b> . <p>
	*
	* For example, if the System properties contains "key=value", then the call
	* <pre>
	*String s = OptionConverter.substituteVars("Value of key is ${key}.");
	*</pre> will set the variable <code>s</code> to "Value of key is value.".
	* <p>
	*
	* If no value could be found for the specified key, then the <code>props</code>
	* parameter is searched, if the value could not be found there, then
	* substitution defaults to the empty string. <p>
	*
	* For example, if system propeties contains no value for the key
	* "inexistentKey", then the call <pre>
	*String s = OptionConverter.subsVars("Value of inexistentKey is [${inexistentKey}]");
	*</pre> will set <code>s</code> to "Value of inexistentKey is []" <p>
	*
	* An {@link java.lang.IllegalArgumentException} is thrown if <code>val</code>
	* contains a start delimeter "${" which is not balanced by a stop delimeter
	* "}". </p> <p>
	*
	* <b>Author</b> Avy Sharell</a> </p>
	*
	* @param val The string on which variable substitution is performed.
	* @throws IllegalArgumentException if <code>val</code> is malformed.
	*/

	public static String substVars( String val, Properties props )
	throws
	IllegalArgumentException
	{
	sbuf.setLength( 0 );

	int i = 0;
	int j;
	int k;

	while ( true )
	{
	j = val.indexOf( DELIM_START, i );
	if ( j == -1 )
	{
	if ( i == 0 )
	{
	return val;
	}
	sbuf.append( val.substring( i, val.length() ) );
	return sbuf.toString();
	}
	sbuf.append( val.substring( i, j ) );
	k = val.indexOf( DELIM_STOP, j );
	if ( k == -1 )
	{
	throw new IllegalArgumentException( '"' + val +
	"\" has no closing brace. Opening brace at position " + j
	+ '.' );
	}
	j += DELIM_START_LEN;
	String key = val.substring( j, k );
	// first try in System properties
	String replacement = getSystemProperty( key, null );
	// then try props parameter
	if ( replacement == null && props != null )
	{
	replacement = props.getProperty( key );
	}

	if ( replacement != null )
	{
	sbuf.append( replacement );
	}
	i = k + DELIM_STOP_LEN;
	}
	}

	}
	// end class