core.com.lowagie.text.Utilities Maven / Gradle / Ivy
/*
* $Id: Utilities.java 3514 2008-06-27 09:26:36Z blowagie $
*
* Copyright 2007 by Bruno Lowagie.
*
* The contents of this file are subject to the Mozilla Public License Version 1.1
* (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.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the License.
*
* The Original Code is 'iText, a free JAVA-PDF library'.
*
* The Initial Developer of the Original Code is Bruno Lowagie. Portions created by
* the Initial Developer are Copyright (C) 1999, 2000, 2001, 2002 by Bruno Lowagie.
* All Rights Reserved.
* Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer
* are Copyright (C) 2000, 2001, 2002 by Paulo Soares. All Rights Reserved.
*
* Contributor(s): all the names of the contributors are added in the source code
* where applicable.
*
* Alternatively, the contents of this file may be used under the terms of the
* LGPL license (the "GNU LIBRARY GENERAL PUBLIC LICENSE"), in which case the
* provisions of LGPL are applicable instead of those above. If you wish to
* allow use of your version of this file only under the terms of the LGPL
* License and not to allow others to use your version of this file under
* the MPL, indicate your decision by deleting the provisions above and
* replace them with the notice and other provisions required by the LGPL.
* If you do not delete the provisions above, a recipient may use your version
* of this file under either the MPL or the GNU LIBRARY GENERAL PUBLIC LICENSE.
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the MPL as stated above or under the terms of the GNU
* Library General Public License as published by the Free Software Foundation;
* either version 2 of the License, or any later version.
*
* This library 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 Library general Public License for more
* details.
*
* If you didn't download this code from the following link, you should check if
* you aren't using an obsolete version:
* http://www.lowagie.com/iText/
*/
package com.lowagie.text;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Collections;
import java.util.Hashtable;
import java.util.Properties;
import java.util.Set;
import com.lowagie.text.pdf.PRTokeniser;
/**
* A collection of convenience methods that were present in many different iText
* classes.
*/
public class Utilities {
/**
* Gets the keys of a Hashtable
*
* @param table
* a Hashtable
* @return the keyset of a Hashtable (or an empty set if table is null)
*/
public static Set getKeySet(Hashtable table) {
return (table == null) ? Collections.EMPTY_SET : table.keySet();
}
/**
* Utility method to extend an array.
*
* @param original
* the original array or null
* @param item
* the item to be added to the array
* @return a new array with the item appended
*/
public static Object[][] addToArray(Object original[][], Object item[]) {
if (original == null) {
original = new Object[1][];
original[0] = item;
return original;
} else {
Object original2[][] = new Object[original.length + 1][];
System.arraycopy(original, 0, original2, 0, original.length);
original2[original.length] = item;
return original2;
}
}
/**
* Checks for a true/false value of a key in a Properties object.
* @param attributes
* @param key
* @return a true/false value of a key in a Properties object
*/
public static boolean checkTrueOrFalse(Properties attributes, String key) {
return "true".equalsIgnoreCase(attributes.getProperty(key));
}
/**
* Unescapes an URL. All the "%xx" are replaced by the 'xx' hex char value.
* @param src the url to unescape
* @return the unescaped value
*/
public static String unEscapeURL(String src) {
StringBuffer bf = new StringBuffer();
char[] s = src.toCharArray();
for (int k = 0; k < s.length; ++k) {
char c = s[k];
if (c == '%') {
if (k + 2 >= s.length) {
bf.append(c);
continue;
}
int a0 = PRTokeniser.getHex(s[k + 1]);
int a1 = PRTokeniser.getHex(s[k + 2]);
if (a0 < 0 || a1 < 0) {
bf.append(c);
continue;
}
bf.append((char)(a0 * 16 + a1));
k += 2;
}
else
bf.append(c);
}
return bf.toString();
}
/**
* This method makes a valid URL from a given filename.
*
* This method makes the conversion of this library from the JAVA 2 platform
* to a JDK1.1.x-version easier.
*
* @param filename
* a given filename
* @return a valid URL
* @throws MalformedURLException
*/
public static URL toURL(String filename) throws MalformedURLException {
try {
return new URL(filename);
}
catch (Exception e) {
return new File(filename).toURI().toURL();
}
}
/**
* This method is an alternative for the InputStream.skip()
* -method that doesn't seem to work properly for big values of size
* .
*
* @param is
* the InputStream
* @param size
* the number of bytes to skip
* @throws IOException
*/
static public void skip(InputStream is, int size) throws IOException {
long n;
while (size > 0) {
n = is.skip(size);
if (n <= 0)
break;
size -= n;
}
}
/**
* Measurement conversion from millimeters to points.
* @param value a value in millimeters
* @return a value in points
* @since 2.1.2
*/
public static final float millimetersToPoints(float value) {
return inchesToPoints(millimetersToInches(value));
}
/**
* Measurement conversion from millimeters to inches.
* @param value a value in millimeters
* @return a value in inches
* @since 2.1.2
*/
public static final float millimetersToInches(float value) {
return value / 25.4f;
}
/**
* Measurement conversion from points to millimeters.
* @param value a value in points
* @return a value in millimeters
* @since 2.1.2
*/
public static final float pointsToMillimeters(float value) {
return inchesToMillimeters(pointsToInches(value));
}
/**
* Measurement conversion from points to inches.
* @param value a value in points
* @return a value in inches
* @since 2.1.2
*/
public static final float pointsToInches(float value) {
return value / 72f;
}
/**
* Measurement conversion from inches to millimeters.
* @param value a value in inches
* @return a value in millimeters
* @since 2.1.2
*/
public static final float inchesToMillimeters(float value) {
return value * 25.4f;
}
/**
* Measurement conversion from inches to points.
* @param value a value in inches
* @return a value in points
* @since 2.1.2
*/
public static final float inchesToPoints(float value) {
return value * 72f;
}
/**
* Check if the value of a character belongs to a certain interval
* that indicates it's the higher part of a surrogate pair.
* @param c the character
* @return true if the character belongs to the interval
* @since 2.1.2
*/
public static boolean isSurrogateHigh(char c) {
return c >= '\ud800' && c <= '\udbff';
}
/**
* Check if the value of a character belongs to a certain interval
* that indicates it's the lower part of a surrogate pair.
* @param c the character
* @return true if the character belongs to the interval
* @since 2.1.2
*/
public static boolean isSurrogateLow(char c) {
return c >= '\udc00' && c <= '\udfff';
}
/**
* Checks if two subsequent characters in a String are
* are the higher and the lower character in a surrogate
* pair (and therefore eligible for conversion to a UTF 32 character).
* @param text the String with the high and low surrogate characters
* @param idx the index of the 'high' character in the pair
* @return true if the characters are surrogate pairs
* @since 2.1.2
*/
public static boolean isSurrogatePair(String text, int idx) {
if (idx < 0 || idx > text.length() - 2)
return false;
return isSurrogateHigh(text.charAt(idx)) && isSurrogateLow(text.charAt(idx + 1));
}
/**
* Checks if two subsequent characters in a character array are
* are the higher and the lower character in a surrogate
* pair (and therefore eligible for conversion to a UTF 32 character).
* @param text the character array with the high and low surrogate characters
* @param idx the index of the 'high' character in the pair
* @return true if the characters are surrogate pairs
* @since 2.1.2
*/
public static boolean isSurrogatePair(char[] text, int idx) {
if (idx < 0 || idx > text.length - 2)
return false;
return isSurrogateHigh(text[idx]) && isSurrogateLow(text[idx + 1]);
}
/**
* Returns the code point of a UTF32 character corresponding with
* a high and a low surrogate value.
* @param highSurrogate the high surrogate value
* @param lowSurrogate the low surrogate value
* @return a code point value
* @since 2.1.2
*/
public static int convertToUtf32(char highSurrogate, char lowSurrogate) {
return (((highSurrogate - 0xd800) * 0x400) + (lowSurrogate - 0xdc00)) + 0x10000;
}
/**
* Converts a unicode character in a character array to a UTF 32 code point value.
* @param text a character array that has the unicode character(s)
* @param idx the index of the 'high' character
* @return the code point value
* @since 2.1.2
*/
public static int convertToUtf32(char[] text, int idx) {
return (((text[idx] - 0xd800) * 0x400) + (text[idx + 1] - 0xdc00)) + 0x10000;
}
/**
* Converts a unicode character in a String to a UTF32 code point value
* @param text a String that has the unicode character(s)
* @param idx the index of the 'high' character
* @return the codepoint value
* @since 2.1.2
*/
public static int convertToUtf32(String text, int idx) {
return (((text.charAt(idx) - 0xd800) * 0x400) + (text.charAt(idx + 1) - 0xdc00)) + 0x10000;
}
/**
* Converts a UTF32 code point value to a String with the corresponding character(s).
* @param codePoint a Unicode value
* @return the corresponding characters in a String
* @since 2.1.2
*/
public static String convertFromUtf32(int codePoint) {
if (codePoint < 0x10000)
return Character.toString((char)codePoint);
codePoint -= 0x10000;
return new String(new char[]{(char)((codePoint / 0x400) + 0xd800), (char)((codePoint % 0x400) + 0xdc00)});
}
}