- /*
- * The Apache Software License, Version 1.1
- *
- * Copyright (c) 1999 The Apache Software Foundation. All rights
- * reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * 3. The end-user documentation included with the redistribution, if
- * any, must include the following acknowlegement:
- * "This product includes software developed by the
- * Apache Software Foundation (http://www.apache.org/)."
- * Alternately, this acknowlegement may appear in the software itself,
- * if and wherever such third-party acknowlegements normally appear.
- *
- * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
- * Foundation" must not be used to endorse or promote products derived
- * from this software without prior written permission. For written
- * permission, please contact apache@apache.org.
- *
- * 5. Products derived from this software may not be called "Apache"
- * nor may "Apache" appear in their names without prior written
- * permission of the Apache Group.
- *
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
- * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
- * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- * ====================================================================
- *
- * This software consists of voluntary contributions made by many
- * individuals on behalf of the Apache Software Foundation. For more
- * information on the Apache Software Foundation, please see
- * <http://www.apache.org/>.
- *
- */
-
- package org.apache.commons.el;
-
- /**
- *
- * <p>An expression representing a String literal value.
- *
- * @author Nathan Abramson - Art Technology Group
- * @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: luehe $
- **/
-
- public class StringLiteral
- extends Literal
- {
- //-------------------------------------
- /**
- *
- * Constructor
- **/
- StringLiteral (Object pValue)
- {
- super (pValue);
- }
-
- //-------------------------------------
- /**
- *
- * Returns a StringLiteral parsed from the given token (enclosed by
- * single or double quotes)
- **/
- public static StringLiteral fromToken (String pToken)
- {
- return new StringLiteral (getValueFromToken (pToken));
- }
-
- //-------------------------------------
- /**
- *
- * Returns a StringLiteral with the given string value
- **/
- public static StringLiteral fromLiteralValue (String pValue)
- {
- return new StringLiteral (pValue);
- }
-
- //-------------------------------------
- /**
- *
- * Parses the given token into the literal value
- **/
- public static String getValueFromToken (String pToken)
- {
- StringBuffer buf = new StringBuffer ();
- int len = pToken.length () - 1;
- boolean escaping = false;
- for (int i = 1; i < len; i++) {
- char ch = pToken.charAt (i);
- if (escaping) {
- buf.append (ch);
- escaping = false;
- }
- else if (ch == '\\') {
- escaping = true;
- }
- else {
- buf.append (ch);
- }
- }
- return buf.toString ();
- }
-
- //-------------------------------------
- /**
- *
- * Converts the specified value to a String token, using " as the
- * enclosing quotes and escaping any characters that need escaping.
- **/
- public static String toStringToken (String pValue)
- {
- // See if any escaping is needed
- if (pValue.indexOf ('\"') < 0 &&
- pValue.indexOf ('\\') < 0) {
- return "\"" + pValue + "\"";
- }
-
- // Escaping is needed
- else {
- StringBuffer buf = new StringBuffer ();
- buf.append ('\"');
- int len = pValue.length ();
- for (int i = 0; i < len; i++) {
- char ch = pValue.charAt (i);
- if (ch == '\\') {
- buf.append ('\\');
- buf.append ('\\');
- }
- else if (ch == '\"') {
- buf.append ('\\');
- buf.append ('\"');
- }
- else {
- buf.append (ch);
- }
- }
- buf.append ('\"');
- return buf.toString ();
- }
- }
-
- //-------------------------------------
- /**
- *
- * Converts the specified value to an identifier token, escaping it
- * as a string literal if necessary.
- **/
- public static String toIdentifierToken (String pValue)
- {
- // See if it's a valid java identifier
- if (isJavaIdentifier (pValue)) {
- return pValue;
- }
-
- // Return as a String literal
- else {
- return toStringToken (pValue);
- }
- }
-
- //-------------------------------------
- /**
- *
- * Returns true if the specified value is a legal java identifier
- **/
- static boolean isJavaIdentifier (String pValue)
- {
- int len = pValue.length ();
- if (len == 0) {
- return false;
- }
- else {
- if (!Character.isJavaIdentifierStart (pValue.charAt (0))) {
- return false;
- }
- else {
- for (int i = 1; i < len; i++) {
- if (!Character.isJavaIdentifierPart (pValue.charAt (i))) {
- return false;
- }
- }
- return true;
- }
- }
- }
-
- //-------------------------------------
- // Expression methods
- //-------------------------------------
- /**
- *
- * Returns the expression in the expression language syntax
- **/
- public String getExpressionString ()
- {
- return toStringToken ((String) getValue ());
- }
-
- //-------------------------------------
- }