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 * 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
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 * 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
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package org.apache.tomcat.util.http.fileupload;

import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;

import org.apache.tomcat.util.http.fileupload.util.mime.MimeUtility;
import org.apache.tomcat.util.http.fileupload.util.mime.RFC2231Utility;

A simple parser intended to parse sequences of name/value pairs. Parameter values are expected to be enclosed in quotes if they contain unsafe characters, such as '=' characters or separators. Parameter values are optional and can be omitted.

param1 = value; param2 = "anything goes; really"; param3

/** * A simple parser intended to parse sequences of name/value pairs. * * Parameter values are expected to be enclosed in quotes if they * contain unsafe characters, such as '=' characters or separators. * Parameter values are optional and can be omitted. * * <p> * {@code param1 = value; param2 = "anything goes; really"; param3} * </p> */
public class ParameterParser {
String to be parsed.
/** * String to be parsed. */
private char[] chars = null;
Current position in the string.
/** * Current position in the string. */
private int pos = 0;
Maximum position in the string.
/** * Maximum position in the string. */
private int len = 0;
Start of a token.
/** * Start of a token. */
private int i1 = 0;
End of a token.
/** * End of a token. */
private int i2 = 0;
Whether names stored in the map should be converted to lower case.
/** * Whether names stored in the map should be converted to lower case. */
private boolean lowerCaseNames = false;
Default ParameterParser constructor.
/** * Default ParameterParser constructor. */
public ParameterParser() { super(); }
Are there any characters left to parse?
Returns:true if there are unparsed characters, false otherwise.
/** * Are there any characters left to parse? * * @return {@code true} if there are unparsed characters, * {@code false} otherwise. */
private boolean hasChar() { return this.pos < this.len; }
A helper method to process the parsed token. This method removes leading and trailing blanks as well as enclosing quotation marks, when necessary.
Params:
  • quoted – true if quotation marks are expected, false otherwise.
Returns:the token
/** * A helper method to process the parsed token. This method removes * leading and trailing blanks as well as enclosing quotation marks, * when necessary. * * @param quoted {@code true} if quotation marks are expected, * {@code false} otherwise. * @return the token */
private String getToken(boolean quoted) { // Trim leading white spaces while ((i1 < i2) && (Character.isWhitespace(chars[i1]))) { i1++; } // Trim trailing white spaces while ((i2 > i1) && (Character.isWhitespace(chars[i2 - 1]))) { i2--; } // Strip away quotation marks if necessary if (quoted && ((i2 - i1) >= 2) && (chars[i1] == '"') && (chars[i2 - 1] == '"')) { i1++; i2--; } String result = null; if (i2 > i1) { result = new String(chars, i1, i2 - i1); } return result; }
Tests if the given character is present in the array of characters.
Params:
  • ch – the character to test for presence in the array of characters
  • charray – the array of characters to test against
Returns:true if the character is present in the array of characters, false otherwise.
/** * Tests if the given character is present in the array of characters. * * @param ch the character to test for presence in the array of characters * @param charray the array of characters to test against * * @return {@code true} if the character is present in the array of * characters, {@code false} otherwise. */
private boolean isOneOf(char ch, final char[] charray) { boolean result = false; for (char element : charray) { if (ch == element) { result = true; break; } } return result; }
Parses out a token until any of the given terminators is encountered.
Params:
  • terminators – the array of terminating characters. Any of these characters when encountered signify the end of the token
Returns:the token
/** * Parses out a token until any of the given terminators * is encountered. * * @param terminators the array of terminating characters. Any of these * characters when encountered signify the end of the token * * @return the token */
private String parseToken(final char[] terminators) { char ch; i1 = pos; i2 = pos; while (hasChar()) { ch = chars[pos]; if (isOneOf(ch, terminators)) { break; } i2++; pos++; } return getToken(false); }
Parses out a token until any of the given terminators is encountered outside the quotation marks.
Params:
  • terminators – the array of terminating characters. Any of these characters when encountered outside the quotation marks signify the end of the token
Returns:the token
/** * Parses out a token until any of the given terminators * is encountered outside the quotation marks. * * @param terminators the array of terminating characters. Any of these * characters when encountered outside the quotation marks signify the end * of the token * * @return the token */
private String parseQuotedToken(final char[] terminators) { char ch; i1 = pos; i2 = pos; boolean quoted = false; boolean charEscaped = false; while (hasChar()) { ch = chars[pos]; if (!quoted && isOneOf(ch, terminators)) { break; } if (!charEscaped && ch == '"') { quoted = !quoted; } charEscaped = (!charEscaped && ch == '\\'); i2++; pos++; } return getToken(true); }
Returns true if parameter names are to be converted to lower case when name/value pairs are parsed.
Returns:true if parameter names are to be converted to lower case when name/value pairs are parsed. Otherwise returns false
/** * Returns {@code true} if parameter names are to be converted to lower * case when name/value pairs are parsed. * * @return {@code true} if parameter names are to be * converted to lower case when name/value pairs are parsed. * Otherwise returns {@code false} */
public boolean isLowerCaseNames() { return this.lowerCaseNames; }
Sets the flag if parameter names are to be converted to lower case when name/value pairs are parsed.
Params:
  • b – true if parameter names are to be converted to lower case when name/value pairs are parsed. false otherwise.
/** * Sets the flag if parameter names are to be converted to lower case when * name/value pairs are parsed. * * @param b {@code true} if parameter names are to be * converted to lower case when name/value pairs are parsed. * {@code false} otherwise. */
public void setLowerCaseNames(boolean b) { this.lowerCaseNames = b; }
Extracts a map of name/value pairs from the given string. Names are expected to be unique. Multiple separators may be specified and the earliest found in the input string is used.
Params:
  • str – the string that contains a sequence of name/value pairs
  • separators – the name/value pairs separators
Returns:a map of name/value pairs
/** * Extracts a map of name/value pairs from the given string. Names are * expected to be unique. Multiple separators may be specified and * the earliest found in the input string is used. * * @param str the string that contains a sequence of name/value pairs * @param separators the name/value pairs separators * * @return a map of name/value pairs */
public Map<String, String> parse(final String str, char[] separators) { if (separators == null || separators.length == 0) { return new HashMap<>(); } char separator = separators[0]; if (str != null) { int idx = str.length(); for (char separator2 : separators) { int tmp = str.indexOf(separator2); if (tmp != -1 && tmp < idx) { idx = tmp; separator = separator2; } } } return parse(str, separator); }
Extracts a map of name/value pairs from the given string. Names are expected to be unique.
Params:
  • str – the string that contains a sequence of name/value pairs
  • separator – the name/value pairs separator
Returns:a map of name/value pairs
/** * Extracts a map of name/value pairs from the given string. Names are * expected to be unique. * * @param str the string that contains a sequence of name/value pairs * @param separator the name/value pairs separator * * @return a map of name/value pairs */
public Map<String, String> parse(final String str, char separator) { if (str == null) { return new HashMap<>(); } return parse(str.toCharArray(), separator); }
Extracts a map of name/value pairs from the given array of characters. Names are expected to be unique.
Params:
  • charArray – the array of characters that contains a sequence of name/value pairs
  • separator – the name/value pairs separator
Returns:a map of name/value pairs
/** * Extracts a map of name/value pairs from the given array of * characters. Names are expected to be unique. * * @param charArray the array of characters that contains a sequence of * name/value pairs * @param separator the name/value pairs separator * * @return a map of name/value pairs */
public Map<String, String> parse(final char[] charArray, char separator) { if (charArray == null) { return new HashMap<>(); } return parse(charArray, 0, charArray.length, separator); }
Extracts a map of name/value pairs from the given array of characters. Names are expected to be unique.
Params:
  • charArray – the array of characters that contains a sequence of name/value pairs
  • offset – - the initial offset.
  • length – - the length.
  • separator – the name/value pairs separator
Returns:a map of name/value pairs
/** * Extracts a map of name/value pairs from the given array of * characters. Names are expected to be unique. * * @param charArray the array of characters that contains a sequence of * name/value pairs * @param offset - the initial offset. * @param length - the length. * @param separator the name/value pairs separator * * @return a map of name/value pairs */
public Map<String, String> parse( final char[] charArray, int offset, int length, char separator) { if (charArray == null) { return new HashMap<>(); } HashMap<String, String> params = new HashMap<>(); this.chars = charArray; this.pos = offset; this.len = length; String paramName = null; String paramValue = null; while (hasChar()) { paramName = parseToken(new char[] { '=', separator }); paramValue = null; if (hasChar() && (charArray[pos] == '=')) { pos++; // skip '=' paramValue = parseQuotedToken(new char[] { separator }); if (paramValue != null) { try { paramValue = RFC2231Utility.hasEncodedValue(paramName) ? RFC2231Utility.decodeText(paramValue) : MimeUtility.decodeText(paramValue); } catch (UnsupportedEncodingException e) { // let's keep the original value in this case } } } if (hasChar() && (charArray[pos] == separator)) { pos++; // skip separator } if ((paramName != null) && (paramName.length() > 0)) { paramName = RFC2231Utility.stripDelimiter(paramName); if (this.lowerCaseNames) { paramName = paramName.toLowerCase(Locale.ENGLISH); } params.put(paramName, paramValue); } } return params; } }