java/org/apache/jasper/tagplugins/jstl/Util.java - tomcat80 - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to You 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.apache.jasper.tagplugins.jstl;

 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.io.StringWriter;
 import java.io.UnsupportedEncodingException;
 import java.util.Locale;

 import javax.servlet.ServletOutputStream;
 import javax.servlet.WriteListener;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpServletResponseWrapper;
 import javax.servlet.jsp.JspException;
 import javax.servlet.jsp.JspTagException;
 import javax.servlet.jsp.PageContext;

 import org.apache.jasper.Constants;

 /**
  * Util contains some often used consts, static methods and embedded class
  * to support the JSTL tag plugin.
  */

 public class Util {

     private static final String VALID_SCHEME_CHAR =
         "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789+.-";

     public static final String DEFAULT_ENCODING =
         "ISO-8859-1";

     private static final int HIGHEST_SPECIAL = '>';

     private static final char[][] specialCharactersRepresentation =
             new char[HIGHEST_SPECIAL + 1][];

     static {
         specialCharactersRepresentation['&'] = "&amp;".toCharArray();
         specialCharactersRepresentation['<'] = "&lt;".toCharArray();
         specialCharactersRepresentation['>'] = "&gt;".toCharArray();
         specialCharactersRepresentation['"'] = "&#034;".toCharArray();
         specialCharactersRepresentation['\''] = "&#039;".toCharArray();
     }

     /**
      * Converts the given string description of a scope to the corresponding
      * PageContext constant.
      *
      * The validity of the given scope has already been checked by the
      * appropriate TLV.
      *
      * @param scope String description of scope
      *
      * @return PageContext constant corresponding to given scope description
      *
      * taken from org.apache.taglibs.standard.tag.common.core.Util
      */
     public static int getScope(String scope){
         int ret = PageContext.PAGE_SCOPE;

         if("request".equalsIgnoreCase(scope)){
             ret = PageContext.REQUEST_SCOPE;
         }else if("session".equalsIgnoreCase(scope)){
             ret = PageContext.SESSION_SCOPE;
         }else if("application".equalsIgnoreCase(scope)){
             ret = PageContext.APPLICATION_SCOPE;
         }

         return ret;
     }

     /**
      * Returns <tt>true</tt> if our current URL is absolute,
      * <tt>false</tt> otherwise.
      * taken from org.apache.taglibs.standard.tag.common.core.ImportSupport
      */
     public static boolean isAbsoluteUrl(String url){
         if(url == null){
             return false;
         }

         int colonPos = url.indexOf(':');
         if(colonPos == -1){
             return false;
         }

         for(int i=0;i<colonPos;i++){
             if(VALID_SCHEME_CHAR.indexOf(url.charAt(i)) == -1){
                 return false;
             }
         }

         return true;
     }

     /**
      * Get the value associated with a content-type attribute.
      * Syntax defined in RFC 2045, section 5.1.
      * taken from org.apache.taglibs.standard.tag.common.core.Util
      */
     public static String getContentTypeAttribute(String input, String name) {
         int begin;
         int end;
         int index = input.toUpperCase(Locale.ENGLISH).indexOf(name.toUpperCase(Locale.ENGLISH));
         if (index == -1) return null;
         index = index + name.length(); // positioned after the attribute name
         index = input.indexOf('=', index); // positioned at the '='
         if (index == -1) return null;
         index += 1; // positioned after the '='
         input = input.substring(index).trim();

         if (input.charAt(0) == '"') {
             // attribute value is a quoted string
             begin = 1;
             end = input.indexOf('"', begin);
             if (end == -1) return null;
         } else {
             begin = 0;
             end = input.indexOf(';');
             if (end == -1) end = input.indexOf(' ');
             if (end == -1) end = input.length();
         }
         return input.substring(begin, end).trim();
     }

     /**
      * Strips a servlet session ID from <tt>url</tt>.  The session ID
      * is encoded as a URL "path parameter" beginning with "jsessionid=".
      * We thus remove anything we find between ";jsessionid=" (inclusive)
      * and either EOS or a subsequent ';' (exclusive).
      *
      * taken from org.apache.taglibs.standard.tag.common.core.ImportSupport
      */
     public static String stripSession(String url) {
         StringBuilder u = new StringBuilder(url);
         int sessionStart;
         while ((sessionStart = u.toString().indexOf(";" + Constants.SESSION_PARAMETER_NAME + "=")) != -1) {
             int sessionEnd = u.toString().indexOf(';', sessionStart + 1);
             if (sessionEnd == -1)
                 sessionEnd = u.toString().indexOf('?', sessionStart + 1);
             if (sessionEnd == -1) // still
                 sessionEnd = u.length();
             u.delete(sessionStart, sessionEnd);
         }
         return u.toString();
     }


     /**
      * Performs the following substring replacements
      * (to facilitate output to XML/HTML pages):
      *
      *    &amp; -&gt; &amp;amp;
      *    &lt; -&gt; &amp;lt;
      *    &gt; -&gt; &amp;gt;
      *    " -&gt; &amp;#034;
      *    ' -&gt; &amp;#039;
      *
      * See also OutSupport.writeEscapedXml().
      *
      * taken from org.apache.taglibs.standard.tag.common.core.Util
      */
     public static String escapeXml(String buffer) {
         String result = escapeXml(buffer.toCharArray(), buffer.length());
         if (result == null) {
             return buffer;
         } else {
             return result;
         }
     }

     @SuppressWarnings("null") // escapedBuffer cannot be null
     public static String escapeXml(char[] arrayBuffer, int length) {
         int start = 0;
         StringBuilder escapedBuffer = null;

         for (int i = 0; i < length; i++) {
             char c = arrayBuffer[i];
             if (c <= HIGHEST_SPECIAL) {
                 char[] escaped = specialCharactersRepresentation[c];
                 if (escaped != null) {
                     // create StringBuilder to hold escaped xml string
                     if (start == 0) {
                         escapedBuffer = new StringBuilder(length + 5);
                     }
                     // add unescaped portion
                     if (start < i) {
                         escapedBuffer.append(arrayBuffer,start,i-start);
                     }
                     start = i + 1;
                     // add escaped xml
                     escapedBuffer.append(escaped);
                 }
             }
         }
         // no xml escaping was necessary
         if (start == 0) {
             return null;
         }
         // add rest of unescaped portion
         if (start < length) {
             escapedBuffer.append(arrayBuffer,start,length-start);
         }
         return escapedBuffer.toString();
     }

     /** Utility methods
      * taken from org.apache.taglibs.standard.tag.common.core.UrlSupport
      */
     public static String resolveUrl(
             String url, String context, PageContext pageContext)
     throws JspException {
         // don't touch absolute URLs
         if (isAbsoluteUrl(url))
             return url;

         // normalize relative URLs against a context root
         HttpServletRequest request =
             (HttpServletRequest) pageContext.getRequest();
         if (context == null) {
             if (url.startsWith("/"))
                 return (request.getContextPath() + url);
             else
                 return url;
         } else {
             if (!context.startsWith("/") || !url.startsWith("/")) {
                 throw new JspTagException(
                 "In URL tags, when the \"context\" attribute is specified, values of both \"context\" and \"url\" must start with \"/\".");
             }
             if (context.equals("/")) {
                 // Don't produce string starting with '//', many
                 // browsers interpret this as host name, not as
                 // path on same host.
                 return url;
             } else {
                 return (context + url);
             }
         }
     }

     /** Wraps responses to allow us to retrieve results as Strings.
      * mainly taken from org.apache.taglibs.standard.tag.common.core.importSupport
      */
     public static class ImportResponseWrapper extends HttpServletResponseWrapper{

         private final StringWriter sw = new StringWriter();
         private final ByteArrayOutputStream bos = new ByteArrayOutputStream();
         private final ServletOutputStream sos = new ServletOutputStream() {
             @Override
             public void write(int b) throws IOException {
                 bos.write(b);
             }

             @Override
             public boolean isReady() {
                 // Non-blocking IO not supported
                 return false;
             }

             @Override
             public void setWriteListener(WriteListener listener) {
                 // Non-blocking IO not supported
                 throw new UnsupportedOperationException();
             }


         };
         private boolean isWriterUsed;
         private boolean isStreamUsed;
         private int status = 200;
         private String charEncoding;

         public ImportResponseWrapper(HttpServletResponse arg0) {
             super(arg0);
             // TODO Auto-generated constructor stub
         }

         @Override
         public PrintWriter getWriter() {
             if (isStreamUsed)
                 throw new IllegalStateException("Unexpected internal error during &lt;import&gt: " +
                 "Target servlet called getWriter(), then getOutputStream()");
             isWriterUsed = true;
             return new PrintWriter(sw);
         }

         @Override
         public ServletOutputStream getOutputStream() {
             if (isWriterUsed)
                 throw new IllegalStateException("Unexpected internal error during &lt;import&gt: " +
                 "Target servlet called getOutputStream(), then getWriter()");
             isStreamUsed = true;
             return sos;
         }

         /** Has no effect. */
         @Override
         public void setContentType(String x) {
             // ignore
         }

         /** Has no effect. */
         @Override
         public void setLocale(Locale x) {
             // ignore
         }

         @Override
         public void setStatus(int status) {
             this.status = status;
         }

         @Override
         public int getStatus() {
             return status;
         }

         public String getCharEncoding(){
             return this.charEncoding;
         }

         public void setCharEncoding(String ce){
             this.charEncoding = ce;
         }

         public String getString() throws UnsupportedEncodingException {
             if (isWriterUsed)
                 return sw.toString();
             else if (isStreamUsed) {
                 if (this.charEncoding != null && !this.charEncoding.equals(""))
                     return bos.toString(charEncoding);
                 else
                     return bos.toString("ISO-8859-1");
             } else
                 return ""; // target didn't write anything
         }
     }

 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You 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.apache.jasper.tagplugins.jstl;

	import java.io.ByteArrayOutputStream;
	import java.io.IOException;
	import java.io.PrintWriter;
	import java.io.StringWriter;
	import java.io.UnsupportedEncodingException;
	import java.util.Locale;

	import javax.servlet.ServletOutputStream;
	import javax.servlet.WriteListener;
	import javax.servlet.http.HttpServletRequest;
	import javax.servlet.http.HttpServletResponse;
	import javax.servlet.http.HttpServletResponseWrapper;
	import javax.servlet.jsp.JspException;
	import javax.servlet.jsp.JspTagException;
	import javax.servlet.jsp.PageContext;

	import org.apache.jasper.Constants;

	/**
	* Util contains some often used consts, static methods and embedded class
	* to support the JSTL tag plugin.
	*/

	public class Util {

	private static final String VALID_SCHEME_CHAR =
	"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789+.-";

	public static final String DEFAULT_ENCODING =
	"ISO-8859-1";

	private static final int HIGHEST_SPECIAL = '>';

	private static final char[][] specialCharactersRepresentation =
	new char[HIGHEST_SPECIAL + 1][];

	static {
	specialCharactersRepresentation['&'] = "&".toCharArray();
	specialCharactersRepresentation['<'] = "<".toCharArray();
	specialCharactersRepresentation['>'] = ">".toCharArray();
	specialCharactersRepresentation['"'] = """.toCharArray();
	specialCharactersRepresentation['\''] = "'".toCharArray();
	}

	/**
	* Converts the given string description of a scope to the corresponding
	* PageContext constant.
	*
	* The validity of the given scope has already been checked by the
	* appropriate TLV.
	*
	* @param scope String description of scope
	*
	* @return PageContext constant corresponding to given scope description
	*
	* taken from org.apache.taglibs.standard.tag.common.core.Util
	*/
	public static int getScope(String scope){
	int ret = PageContext.PAGE_SCOPE;

	if("request".equalsIgnoreCase(scope)){
	ret = PageContext.REQUEST_SCOPE;
	}else if("session".equalsIgnoreCase(scope)){
	ret = PageContext.SESSION_SCOPE;
	}else if("application".equalsIgnoreCase(scope)){
	ret = PageContext.APPLICATION_SCOPE;
	}

	return ret;
	}

	/**
	* Returns <tt>true</tt> if our current URL is absolute,
	* <tt>false</tt> otherwise.
	* taken from org.apache.taglibs.standard.tag.common.core.ImportSupport
	*/
	public static boolean isAbsoluteUrl(String url){
	if(url == null){
	return false;
	}

	int colonPos = url.indexOf(':');
	if(colonPos == -1){
	return false;
	}

	for(int i=0;i<colonPos;i++){
	if(VALID_SCHEME_CHAR.indexOf(url.charAt(i)) == -1){
	return false;
	}
	}

	return true;
	}

	/**
	* Get the value associated with a content-type attribute.
	* Syntax defined in RFC 2045, section 5.1.
	* taken from org.apache.taglibs.standard.tag.common.core.Util
	*/
	public static String getContentTypeAttribute(String input, String name) {
	int begin;
	int end;
	int index = input.toUpperCase(Locale.ENGLISH).indexOf(name.toUpperCase(Locale.ENGLISH));
	if (index == -1) return null;
	index = index + name.length(); // positioned after the attribute name
	index = input.indexOf('=', index); // positioned at the '='
	if (index == -1) return null;
	index += 1; // positioned after the '='
	input = input.substring(index).trim();

	if (input.charAt(0) == '"') {
	// attribute value is a quoted string
	begin = 1;
	end = input.indexOf('"', begin);
	if (end == -1) return null;
	} else {
	begin = 0;
	end = input.indexOf(';');
	if (end == -1) end = input.indexOf(' ');
	if (end == -1) end = input.length();
	}
	return input.substring(begin, end).trim();
	}

	/**
	* Strips a servlet session ID from <tt>url</tt>. The session ID
	* is encoded as a URL "path parameter" beginning with "jsessionid=".
	* We thus remove anything we find between ";jsessionid=" (inclusive)
	* and either EOS or a subsequent ';' (exclusive).
	*
	* taken from org.apache.taglibs.standard.tag.common.core.ImportSupport
	*/
	public static String stripSession(String url) {
	StringBuilder u = new StringBuilder(url);
	int sessionStart;
	while ((sessionStart = u.toString().indexOf(";" + Constants.SESSION_PARAMETER_NAME + "=")) != -1) {
	int sessionEnd = u.toString().indexOf(';', sessionStart + 1);
	if (sessionEnd == -1)
	sessionEnd = u.toString().indexOf('?', sessionStart + 1);
	if (sessionEnd == -1) // still
	sessionEnd = u.length();
	u.delete(sessionStart, sessionEnd);
	}
	return u.toString();
	}


	/**
	* Performs the following substring replacements
	* (to facilitate output to XML/HTML pages):
	*
	* & -> &amp;
	* < -> &lt;
	* > -> &gt;
	* " -> &#034;
	* ' -> &#039;
	*
	* See also OutSupport.writeEscapedXml().
	*
	* taken from org.apache.taglibs.standard.tag.common.core.Util
	*/
	public static String escapeXml(String buffer) {
	String result = escapeXml(buffer.toCharArray(), buffer.length());
	if (result == null) {
	return buffer;
	} else {
	return result;
	}
	}

	@SuppressWarnings("null") // escapedBuffer cannot be null
	public static String escapeXml(char[] arrayBuffer, int length) {
	int start = 0;
	StringBuilder escapedBuffer = null;

	for (int i = 0; i < length; i++) {
	char c = arrayBuffer[i];
	if (c <= HIGHEST_SPECIAL) {
	char[] escaped = specialCharactersRepresentation[c];
	if (escaped != null) {
	// create StringBuilder to hold escaped xml string
	if (start == 0) {
	escapedBuffer = new StringBuilder(length + 5);
	}
	// add unescaped portion
	if (start < i) {
	escapedBuffer.append(arrayBuffer,start,i-start);
	}
	start = i + 1;
	// add escaped xml
	escapedBuffer.append(escaped);
	}
	}
	}
	// no xml escaping was necessary
	if (start == 0) {
	return null;
	}
	// add rest of unescaped portion
	if (start < length) {
	escapedBuffer.append(arrayBuffer,start,length-start);
	}
	return escapedBuffer.toString();
	}

	/** Utility methods
	* taken from org.apache.taglibs.standard.tag.common.core.UrlSupport
	*/
	public static String resolveUrl(
	String url, String context, PageContext pageContext)
	throws JspException {
	// don't touch absolute URLs
	if (isAbsoluteUrl(url))
	return url;

	// normalize relative URLs against a context root
	HttpServletRequest request =
	(HttpServletRequest) pageContext.getRequest();
	if (context == null) {
	if (url.startsWith("/"))
	return (request.getContextPath() + url);
	else
	return url;
	} else {
	if (!context.startsWith("/") \|\| !url.startsWith("/")) {
	throw new JspTagException(
	"In URL tags, when the \"context\" attribute is specified, values of both \"context\" and \"url\" must start with \"/\".");
	}
	if (context.equals("/")) {
	// Don't produce string starting with '//', many
	// browsers interpret this as host name, not as
	// path on same host.
	return url;
	} else {
	return (context + url);
	}
	}
	}

	/** Wraps responses to allow us to retrieve results as Strings.
	* mainly taken from org.apache.taglibs.standard.tag.common.core.importSupport
	*/
	public static class ImportResponseWrapper extends HttpServletResponseWrapper{

	private final StringWriter sw = new StringWriter();
	private final ByteArrayOutputStream bos = new ByteArrayOutputStream();
	private final ServletOutputStream sos = new ServletOutputStream() {
	@Override
	public void write(int b) throws IOException {
	bos.write(b);
	}

	@Override
	public boolean isReady() {
	// Non-blocking IO not supported
	return false;
	}

	@Override
	public void setWriteListener(WriteListener listener) {
	// Non-blocking IO not supported
	throw new UnsupportedOperationException();
	}



	};
	private boolean isWriterUsed;
	private boolean isStreamUsed;
	private int status = 200;
	private String charEncoding;

	public ImportResponseWrapper(HttpServletResponse arg0) {
	super(arg0);
	// TODO Auto-generated constructor stub
	}

	@Override
	public PrintWriter getWriter() {
	if (isStreamUsed)
	throw new IllegalStateException("Unexpected internal error during <import&gt: " +
	"Target servlet called getWriter(), then getOutputStream()");
	isWriterUsed = true;
	return new PrintWriter(sw);
	}

	@Override
	public ServletOutputStream getOutputStream() {
	if (isWriterUsed)
	throw new IllegalStateException("Unexpected internal error during <import&gt: " +
	"Target servlet called getOutputStream(), then getWriter()");
	isStreamUsed = true;
	return sos;
	}

	/** Has no effect. */
	@Override
	public void setContentType(String x) {
	// ignore
	}

	/** Has no effect. */
	@Override
	public void setLocale(Locale x) {
	// ignore
	}

	@Override
	public void setStatus(int status) {
	this.status = status;
	}

	@Override
	public int getStatus() {
	return status;
	}

	public String getCharEncoding(){
	return this.charEncoding;
	}

	public void setCharEncoding(String ce){
	this.charEncoding = ce;
	}

	public String getString() throws UnsupportedEncodingException {
	if (isWriterUsed)
	return sw.toString();
	else if (isStreamUsed) {
	if (this.charEncoding != null && !this.charEncoding.equals(""))
	return bos.toString(charEncoding);
	else
	return bos.toString("ISO-8859-1");
	} else
	return ""; // target didn't write anything
	}
	}

	}