com.Ostermiller.util.CGIParser Maven / Gradle / Ivy
/*
* Parse CGI query data.
* Copyright (C) 2001-2004 Stephen Ostermiller
* http://ostermiller.org/contact.pl?regarding=Java+Utilities
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* See COPYING.TXT for details.
*/
package com.Ostermiller.util;
import java.io.*;
import java.net.URLDecoder;
import java.util.*;
/**
* Parses query string data from a CGI request into name value pairs.
*
* More information about this class is available from ostermiller.org.
*
* @author Stephen Ostermiller http://ostermiller.org/contact.pl?regarding=Java+Utilities
* @since ostermillerutils 1.00.00
*/
public class CGIParser {
/**
* Hash of names to Array Lists of values.
*/
private HashMap> nameValuePairHash = new HashMap>();
/**
* Array list of NameValuePair objects.
*/
private LinkedList nameValuePairList = new LinkedList();
/**
* Extract the name, value pairs from the given input stream and
* make them available for retrieval.
*
* The stream is read until the stream contains no more bytes.
*
* Byte to character conversion on the stream is done according the platforms
* default character encoding.
*
* @param in Stream containing CGI Encoded name value pairs.
* @throws IOException If an input error occurs
* @deprecated This method does not decode URLEncoded values properly. Please use a method that specifies a character set.
*
* @since ostermillerutils 1.00.00
*/
@Deprecated public CGIParser(InputStream in) throws IOException {
if (in == null) return;
CGILexer lex = new CGILexer(in);
parse(lex, "ISO-8859-1");
}
/**
* Extract the name, value pairs from the given input stream and
* make them available for retrieval.
*
* The stream is read until the stream contains no more bytes.
*
* The character set is used both when converting the byte stream to
* a character stream and when decoding URL decoded parameters.
*
* @param in Stream containing CGI Encoded name value pairs.
* @param charset Character encoding to use when converting bytes to characters
* @throws IOException If an input error occurs
* @throws UnsupportedEncodingException If the character set provided is not recognized
*
* @since ostermillerutils 1.03.00
*/
public CGIParser(InputStream in, String charset) throws IOException, UnsupportedEncodingException {
if (in == null) return;
CGILexer lex = new CGILexer(new InputStreamReader(in, charset));
parse(lex, charset);
}
/**
* Extract the name, value pairs from the given reader and
* make them available for retrieval.
*
* The reader is read until the stream contains no more characters.
*
* @param in Reader containing CGI Encoded name value pairs.
* @throws IOException If an input error occurs
* @deprecated This method does not decode URLEncoded values properly. Please use a method that specifies a character set.
*
* @since ostermillerutils 1.00.00
*/
@Deprecated public CGIParser(Reader in) throws IOException {
if (in == null) return;
CGILexer lex = new CGILexer(in);
parse(lex, "ISO-8859-1");
}
/**
* Extract the name, value pairs from the given reader and
* make them available for retrieval.
*
* The reader is read until the stream contains no more characters.
*
* @param in Reader containing CGI Encoded name value pairs.
* @param charset Character encoding to use when converting bytes to characters
* @throws IOException If an input error occurs
* @throws UnsupportedEncodingException If the character set provided is not recognized
*
* @since ostermillerutils 1.03.00
*/
public CGIParser(Reader in, String charset) throws IOException, UnsupportedEncodingException {
if (in == null) return;
CGILexer lex = new CGILexer(in);
parse(lex, charset);
}
/**
* Extract the name, value pairs from the given string and
* make them available for retrieval.
*
* @param s CGI Encoded name value pairs.
* @deprecated This method does not decode URLEncoded values properly. Please use a method that specifies a character set.
*
* @since ostermillerutils 1.00.00
*/
@Deprecated public CGIParser(String s){
if (s == null) return;
try {
CGILexer lex = new CGILexer(new StringReader(s));
parse(lex, "ISO-8859-1");
} catch (IOException x){
// This shouldn't be able to happen from a string.
throw new RuntimeException(x);
}
}
/**
* Extract the name, value pairs from the given string and
* make them available for retrieval.
*
* @param s CGI Encoded name value pairs.
* @param charset Character encoding to use when converting bytes to characters
* @throws UnsupportedEncodingException If the character set provided is not recognized
*
* @since ostermillerutils 1.03.00
*/
public CGIParser(String s, String charset) throws UnsupportedEncodingException {
if (s == null) return;
try {
CGILexer lex = new CGILexer(new StringReader(s));
parse(lex, charset);
} catch (UnsupportedEncodingException uex){
throw uex;
} catch (IOException x){
// This shouldn't be able to happen from a string.
throw new RuntimeException(x);
}
}
/**
* Retrieve the name value pairs from the lexer and hash
* them in the CGI hash table.
*
* @param lex Lexer that will return the tokens.
* @throws IOException If an input error occurs
*
* @since ostermillerutils 1.00.00
*/
private void parse(CGILexer lex, String charset) throws IOException, UnsupportedEncodingException {
String nameValue, name, value;
while ((nameValue = lex.nextToken()) != null) {
int equalInd = nameValue.indexOf("=");
if (equalInd == -1){
name = nameValue;
value = "";
} else {
name = nameValue.substring(0, equalInd);
value = nameValue.substring(equalInd+1, nameValue.length());
}
try {
name = URLDecoder.decode(name, charset);
} catch (IllegalArgumentException iax){
// May be thrown for for illegal escape sequences such as %s
name = "";
}
try {
value = URLDecoder.decode(value, charset);
} catch (IllegalArgumentException iax){
// May be thrown for for illegal escape sequences such as %s
value = "";
}
// Hash
ArrayList values = nameValuePairHash.get(name);
if (values == null){
values = new ArrayList();
}
values.add(value);
nameValuePairHash.put(name, values);
// List
nameValuePairList.add(new NameValuePair(name, value));
}
}
/**
* Returns an array of String objects containing all of the values the given request
* parameter has, or null if the parameter does not exist.
*
* If the parameter has a single value, the array has a length of 1.
* @param name a String containing the name of the parameter whose value is requested
* @return an array of String objects containing the parameter's values
*
* @since ostermillerutils 1.00.00
*/
public String[] getParameterValues(String name){
ArrayList values = nameValuePairHash.get(name);
if (values == null){
return null;
}
String[] valArray = new String[values.size()];
return (values.toArray(valArray));
}
/**
* Set a name value pair as used in a URL.
* This method will replace any previously defined values with the single
* value specified. If the value is null, the name is removed.
*
* @param name a String specifying the name of the parameter.
* @param value a String specifying the value of the single parameter, or null to remove.
*
* @since ostermillerutils 1.02.15
*/
public void setParameter(String name, String value){
Iterator listIterator = nameValuePairList.iterator();
while (listIterator.hasNext()){
NameValuePair nameValuePair = listIterator.next();
if (nameValuePair.getName().equals(name)){
listIterator.remove();
}
}
if (value == null){
nameValuePairHash.remove(name);
return;
}
ArrayList values = nameValuePairHash.get(name);
if (values == null){
values = new ArrayList();
}
values.clear();
values.add(value);
nameValuePairHash.put(name, values);
nameValuePairList.add(new NameValuePair(name, value));
}
/**
* Set a name value pair as used in a URL.
* This method will replace any previously defined values with the single
* value specified. If values is null or empty, the name is removed.
*
* @param name a String specifying the name of the parameter.
* @param values a String array specifying the values for the parameter, or null to remove.
* @throws NullPointerException if any of the values is null.
*
* @since ostermillerutils 1.02.15
*/
public void setParameter(String name, String[] values){
Iterator listIterator = nameValuePairList.iterator();
while (listIterator.hasNext()){
NameValuePair nameValuePair = listIterator.next();
if (nameValuePair.getName().equals(name)){
listIterator.remove();
}
}
if (values == null || values.length == 0){
nameValuePairHash.remove(name);
return;
}
for (String element: values) {
if (element == null) throw new NullPointerException();
}
ArrayList valuesVec = nameValuePairHash.get(name);
if (valuesVec == null){
valuesVec = new ArrayList();
}
valuesVec.clear();
for (String element: values) {
valuesVec.add(element);
nameValuePairList.add(new NameValuePair(name, element));
}
nameValuePairHash.put(name, valuesVec);
}
/**
* Set a name value pair as used in a URL.
* This method will add to any previously defined values the values
* specified. If value is null, this method has no effect.
*
* @param name a String specifying the name of the parameter.
* @param value a String specifying the value of the single parameter, or null to remove.
*
* @since ostermillerutils 1.02.15
*/
public void addParameter(String name, String value){
if (value == null){
return;
}
ArrayList values = nameValuePairHash.get(name);
if (values == null){
values = new ArrayList();
}
values.add(value);
nameValuePairHash.put(name, values);
nameValuePairList.add(new NameValuePair(name, value));
}
/**
* Set a name value pair as used in a URL.
* This method will add to any previously defined values the values
* specified. If values is null, this method has no effect.
*
* @param name a String specifying the name of the parameter.
* @param values a String array specifying the values of the parameter, or null to remove.
* @throws NullPointerException if any of the values is null.
*
* @since ostermillerutils 1.02.15
*/
public void addParameter(String name, String[] values){
if (values == null || values.length == 0){
return;
}
for (String element: values) {
if (element == null) throw new NullPointerException();
}
ArrayList valuesVec = nameValuePairHash.get(name);
if (valuesVec == null){
valuesVec = new ArrayList();
}
for (String element: values) {
valuesVec.add(element);
nameValuePairList.add(new NameValuePair(name, element));
}
nameValuePairHash.put(name, valuesVec);
}
/**
* Returns the value of a request parameter as a String, or null if the parameter does
* not exist. Request parameters are extra information sent with the request.
*
* You should only use this method when you are sure the parameter has only one value.
* If the parameter might have more than one value, use getParameterValues(java.lang.String).
*
* If you use this method with a multiple valued parameter, the value returned is equal to
* the first value in the array returned by getParameterValues.
*
* @param name a String specifying the name of the parameter
* @return a String representing the single value of the parameter
*
* @since ostermillerutils 1.00.00
*/
public String getParameter(String name){
ArrayList values = nameValuePairHash.get(name);
if (values == null){
return null;
}
return (values.get(0));
}
/**
* Returns an Enumeration of String objects containing the names of the
* parameters contained in this request. If the request has no parameters,
* the method returns an empty Enumeration.
*
* @return an Enumeration of String objects, each String containing the name
* of a request parameter; or an empty Enumeration if the request has
* no parameters
*
* @since ostermillerutils 1.00.00
*/
public Enumeration getParameterNames(){
return new IteratorEnumeration(nameValuePairHash.keySet().iterator());
}
/**
* Returns the names of the
* parameters contained in this request. If the request has no parameters,
* the method returns an empty String array. Each name will appear only
* once, even if it was contained in the request multiple times. The order
* of the names may not match the order from the request.
*
* @return An array of Strings, each of which is the name
* of a request parameter; or an array of length zero if the request has
* no parameters
*
* @since ostermillerutils 1.03.00
*/
public String[] getParameterNameList(){
return nameValuePairHash.keySet().toArray(new String[0]);
}
/**
* Get the all the parameters in the order in which they were added.
*
* @return array of all name value pairs.
*/
public NameValuePair[] getParameters(){
return nameValuePairList.toArray(new NameValuePair[0]);
}
/**
* Returns the name value pairs properly escaped and written in URL format.
*
* @param enc Character encoding to use when escaping characters.
* @return URLEncoded name value pairs.
* @throws UnsupportedEncodingException If the named encoding is not supported.
*
* @since ostermillerutils 1.00.00
*/
public String toString(String enc) throws UnsupportedEncodingException {
StringBuffer sb = new StringBuffer();
boolean bFirst = true;
Iterator listIterator = nameValuePairList.iterator();
while (listIterator.hasNext()){
NameValuePair nameValuePair = listIterator.next();
if (!bFirst) sb.append('&');
bFirst = false;
sb.append(nameValuePair.toString(enc));
}
return sb.toString();
}
/**
* Returns the name value pairs properly escaped and written in URL format
* with UTF-8 URL encoding.
*
* @return URLEncoded name value pairs.
*
* @since ostermillerutils 1.03.00
*/
@Override public String toString() {
try {
return toString("UTF-8");
} catch (UnsupportedEncodingException uex){
// UTF-8 should be supported
throw new RuntimeException(uex);
}
}
}