package org.jboss.resteasy.util;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

A simple parser intended to parse sequences of name/value pairs. Parameter values are exptected 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

Author:Oleg Kalnichevski
/** * A simple parser intended to parse sequences of name/value pairs. * Parameter values are exptected 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</code> * </p> * * @author <a href="mailto:oleg@ural.ru">Oleg Kalnichevski</a> */
public class GroupParameterParser {
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 GroupParameterParser() { 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</code> if there are unparsed characters, * <code>false</code> 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</code> if quotation marks are expected, * <code>false</code> 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) { if (((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 presense 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 presense in the array of characters * @param charray the array of characters to test against * @return <code>true</code> if the character is present in the array of * characters, <code>false</code> otherwise. */
private boolean isOneOf(char ch, final char[] charray) { boolean result = false; for (int i = 0; i < charray.length; i++) { if (ch == charray[i]) { 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</code> if parameter names are to be converted to lower * case when name/value pairs are parsed. * * @return <code>true</code> if parameter names are to be * converted to lower case when name/value pairs are parsed. * Otherwise returns <code>false</code> */
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</code> if parameter names are to be * converted to lower case when name/value pairs are parsed. * <code>false</code> 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.
Params:
  • str – the string that contains a sequence of name/value pairs
  • separator – the name/value pairs separator
  • groupSeparator – group 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 * @param groupSeparator group separator * @return a map of name/value pairs */
public List<Map<String, String>> parse(final String str, char separator, char groupSeparator) { if (str == null) { return new ArrayList<Map<String, String>>(); } return parse(str.toCharArray(), separator, groupSeparator); }
Extracts a map of name/value pairs from the given array of characters. Names are expected to be unique.
Params:
  • chars – the array of characters that contains a sequence of name/value pairs
  • separator – the name/value pairs separator
  • groupSeparator – group 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 chars the array of characters that contains a sequence of * name/value pairs * @param separator the name/value pairs separator * @param groupSeparator group separator * @return a map of name/value pairs */
public List<Map<String, String>> parse(final char[] chars, char separator, char groupSeparator) { if (chars == null) { return new ArrayList<Map<String, String>>(); } return parse(chars, 0, chars.length, separator, groupSeparator); }
Extracts a map of name/value pairs from the given array of characters. Names are expected to be unique.
Params:
  • chars – 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
  • groupSeparator – group 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 chars 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 * @param groupSeparator group separator * @return a map of name/value pairs */
public List<Map<String, String>> parse( final char[] chars, int offset, int length, char separator, char groupSeparator) { if (chars == null) { return new ArrayList<Map<String, String>>(); } List<Map<String, String>> groups = new ArrayList<Map<String, String>>(); HashMap<String, String> params = new HashMap<String, String>(); groups.add(params); this.chars = chars; this.pos = offset; this.len = length; String paramName = null; String paramValue = null; while (hasChar()) { paramName = parseToken(new char[]{'=', separator, groupSeparator}); paramValue = null; if (hasChar() && (chars[pos] == '=')) { pos++; // skip '=' paramValue = parseQuotedToken(new char[]{ separator, groupSeparator}); } if ((paramName != null) && (paramName.length() > 0)) { if (this.lowerCaseNames) { paramName = paramName.toLowerCase(); } params.put(paramName, paramValue); } if (hasChar() && (chars[pos] == separator)) { pos++; // skip separator } else if (hasChar() && (chars[pos] == groupSeparator)) { pos++; // skip separator params = new HashMap<String, String>(); groups.add(params); } } return groups; } }