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Apache XML Graphics Commons is a library that consists of several reusable
components used by Apache Batik and Apache FOP. Many of these components
can easily be used separately outside the domains of SVG and XSL-FO.
/*
* 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.
*/
/* $Id: PSDictionary.java 1681108 2015-05-22 13:26:12Z ssteiner $ */
package org.apache.xmlgraphics.ps;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.StringTokenizer;
// CSOFF: InnerAssignment
/**
* This class is used to encapsulate postscript dictionary objects.
*/
public class PSDictionary extends java.util.HashMap {
private static final long serialVersionUID = 815367222496219197L;
/**
* This class is used to parse dictionary strings.
*/
private static class Maker {
/**
* Simple token holding class
*/
private static class Token {
/**
* start index in string
*/
private int startIndex = -1;
/**
* end index in string
*/
private int endIndex = -1;
/**
* token string value
*/
private String value;
}
private static final String[][] BRACES = {
{"<<", ">>"},
{"[", "]"},
{"{", "}"},
{"(", ")"}
};
private static final int OPENING = 0;
private static final int CLOSING = 1;
private static final int DICTIONARY = 0;
private static final int ARRAY = 1;
private static final int PROCEDURE = 2;
private static final int STRING = 3;
/**
* Returns a Token containing the start, end index and value of the next token
* found in a given string
*
* @param str
* string to search
* @param fromIndex
* search from index
* @return Token containing the start, end index and value of the next token
*/
protected Token nextToken(String str, int fromIndex) {
Token t = null;
for (int i = fromIndex; i < str.length(); i++) {
boolean isWhitespace = Character.isWhitespace(str.charAt(i));
// start index found
if (t == null && !isWhitespace) {
t = new Token();
t.startIndex = i;
// end index found
} else if (t != null && isWhitespace) {
t.endIndex = i;
break;
}
}
// start index found
if (t != null) {
// end index not found so take end of string
if (t.endIndex == -1) {
t.endIndex = str.length();
}
t.value = str.substring(t.startIndex, t.endIndex);
}
return t;
}
/**
* Returns the closing brace index from a given string searches from a
* given index
*
* @param str
* string to search
* @param braces
* string array of opening and closing brace
* @param fromIndex
* searches from index
* @return matching brace index
* @throws org.apache.xmlgraphics.ps.PSDictionaryFormatException
* thrown in the event that a parsing error occurred
*/
private int indexOfMatchingBrace(String str, String[] braces,
int fromIndex) throws PSDictionaryFormatException {
final int len = str.length();
if (braces.length != 2) {
throw new PSDictionaryFormatException("Wrong number of braces");
}
for (int openCnt = 0, closeCnt = 0; fromIndex < len; fromIndex++) {
if (str.startsWith(braces[OPENING], fromIndex)) {
openCnt++;
} else if (str.startsWith(braces[CLOSING], fromIndex)) {
closeCnt++;
if (openCnt > 0 && openCnt == closeCnt) {
return fromIndex; // found
}
}
}
return -1; // not found
}
/**
* Strips braces from complex object string
*
* @param str
* String to parse
* @param braces
* String array containing opening and closing braces
* @return String with braces stripped
* @throws org.apache.xmlgraphics.ps.PSDictionaryFormatException
* thrown in the event that a parsing error occurred
*/
private String stripBraces(String str, String[] braces) throws PSDictionaryFormatException {
// find first opening brace
int firstIndex = str.indexOf(braces[OPENING]);
if (firstIndex == -1) {
throw new PSDictionaryFormatException(
"Failed to find opening parameter '" + braces[OPENING]
+ "");
}
// find last matching brace
int lastIndex = indexOfMatchingBrace(str, braces, firstIndex);
if (lastIndex == -1) {
throw new PSDictionaryFormatException(
"Failed to find matching closing parameter '"
+ braces[CLOSING] + "'");
}
// strip brace and trim
int braceLen = braces[OPENING].length();
str = str.substring(firstIndex + braceLen, lastIndex).trim();
return str;
}
/**
* Parses a dictionary string and provides a dictionary object
*
* @param str a dictionary string
* @return A postscript dictionary object
* @throws org.apache.xmlgraphics.ps.PSDictionaryFormatException
* thrown in the event that a parsing error occurred
*/
public PSDictionary parseDictionary(String str) throws PSDictionaryFormatException {
PSDictionary dictionary = new PSDictionary();
str = stripBraces(str.trim(), BRACES[DICTIONARY]);
// length of dictionary string
final int len = str.length();
Token keyToken;
for (int currIndex = 0; (keyToken = nextToken(str, currIndex)) != null
&& currIndex <= len;) {
if (keyToken.value == null) {
throw new PSDictionaryFormatException("Failed to parse object key");
}
Token valueToken = nextToken(str, keyToken.endIndex + 1);
String[] braces = null;
for (int i = 0; i < BRACES.length; i++) {
if (valueToken.value.startsWith(BRACES[i][OPENING])) {
braces = BRACES[i];
break;
}
}
Object obj = null;
if (braces != null) {
// find closing brace
valueToken.endIndex = indexOfMatchingBrace(str, braces,
valueToken.startIndex)
+ braces[OPENING].length();
if (valueToken.endIndex < 0) {
throw new PSDictionaryFormatException("Closing value brace '"
+ braces[CLOSING] + "' not found for key '"
+ keyToken.value + "'");
}
valueToken.value = str.substring(valueToken.startIndex, valueToken.endIndex);
}
if (braces == null || braces == BRACES[PROCEDURE] || braces == BRACES[STRING]) {
obj = valueToken.value;
} else if (BRACES[ARRAY] == braces) {
List objList = new java.util.ArrayList();
String objString = stripBraces(valueToken.value, braces);
StringTokenizer tokenizer = new StringTokenizer(objString, ",");
while (tokenizer.hasMoreTokens()) {
objList.add(tokenizer.nextToken());
}
obj = objList;
} else if (BRACES[DICTIONARY] == braces) {
obj = parseDictionary(valueToken.value);
}
dictionary.put(keyToken.value, obj);
currIndex = valueToken.endIndex + 1;
}
return dictionary;
}
}
/**
* Parses a given a dictionary string and returns an object
*
* @param str dictionary string
* @return dictionary object
* @throws org.apache.xmlgraphics.ps.PSDictionaryFormatException
* thrown in the event that a parsing error occurred
*/
public static PSDictionary valueOf(String str) throws PSDictionaryFormatException {
return (new Maker()).parseDictionary(str);
}
/**
* @param obj object to test equality against
* @return whether a given object is equal to this dictionary object
* @see java.lang.Object#equals(Object)
*/
public boolean equals(Object obj) {
if (!(obj instanceof PSDictionary)) {
return false;
}
PSDictionary dictionaryObj = (PSDictionary) obj;
if (dictionaryObj.size() != size()) {
return false;
}
for (Object e : entrySet()) {
Map.Entry entry = (Map.Entry) e;
String key = (String) entry.getKey();
if (!dictionaryObj.containsKey(key)) {
return false;
}
if (!dictionaryObj.get(key).equals(entry.getValue())) {
return false;
}
}
return true;
}
/** {@inheritDoc} */
public int hashCode() {
int hashCode = 7;
for (Iterator it = values().iterator(); it.hasNext();) {
Object value = it.next();
hashCode += value.hashCode();
}
return hashCode;
}
/** {@inheritDoc} */
public String toString() {
if (isEmpty()) {
return "";
}
StringBuffer sb = new StringBuffer("<<\n");
for (Iterator it = super.keySet().iterator(); it.hasNext();) {
String key = (String) it.next();
sb.append(" " + key + " ");
Object obj = super.get(key);
if (obj instanceof java.util.ArrayList) {
List array = (List)obj;
StringBuilder str = new StringBuilder("[");
for (int i = 0; i < array.size(); i++) {
Object element = array.get(i);
str.append(element + " ");
}
String str2 = str.toString().trim();
str2 += "]";
sb.append(str2 + "\n");
} else {
sb.append(obj.toString() + "\n");
}
}
sb.append(">>");
return sb.toString();
}
}