All Downloads are FREE. Search and download functionalities are using the official Maven repository.

org.jasypt.normalization.Normalizer Maven / Gradle / Ivy

There is a newer version: 6.1.3
Show newest version
/*
 * =============================================================================
 * 
 *   Copyright (c) 2007-2010, The JASYPT team (http://www.jasypt.org)
 * 
 *   Licensed 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.
 * 
 * =============================================================================
 */
package org.jasypt.normalization;

import java.lang.reflect.Field;
import java.lang.reflect.Method;

import org.jasypt.exceptions.EncryptionInitializationException;


/**
 * 

* Utility for the normalization of Unicode Strings to NFC form. *

*

* This class tries to use the java.text.Normalizer class in JDK 1.6 * first and, if it the class is not found (Java version < 6), then it will use * the ICU4J com.ibm.icu.text.Normalizer class (in this case, a * ClassNotFoundException will be thrown if ICU4J is not present). *

* * @since 1.5 * * @author Daniel Fernández * */ public final class Normalizer { private static final String ICU_NORMALIZER_CLASS_NAME = "com.ibm.icu.text.Normalizer"; private static final String JDK_NORMALIZER_CLASS_NAME = "java.text.Normalizer"; private static final String JDK_NORMALIZER_FORM_CLASS_NAME = "java.text.Normalizer$Form"; private static Boolean useIcuNormalizer = null; private static Method javaTextNormalizerMethod = null; private static Object javaTextNormalizerFormNFCConstant = null; /** *

* Normalize Unicode-input message to NFC. *

*

* This algorithm will first try to normalize the input's UNICODE using icu4j's * com.ibm.icu.text.Normalizer and, if it is not present at the * classpath, will try to use java.text.Normalizer. If this is not present * either (this class appeared in JavaSE 6), it will raise an exception. *

* * @param message the message to be normalized * @return the result of the normalization operation */ public static String normalizeToNfc(final String message) { return new String(normalizeToNfc(message.toCharArray())); } /** *

* Normalize Unicode-input message to NFC. *

*

* This algorithm will first try to normalize the input's UNICODE using icu4j's * com.ibm.icu.text.Normalizer and, if it is not present at the * classpath, will try to use java.text.Normalizer. If this is not present * either (this class appeared in JavaSE 6), it will raise an exception. *

* * @param message the message to be normalized * @return the result of the normalization operation */ public static char[] normalizeToNfc(final char[] message) { if (useIcuNormalizer == null) { // Still not initialized, will try to load the icu4j Normalizer. If // icu4j is in the classpath, it will be used even if java version is >= 6. try { initializeIcu4j(); } catch (final ClassNotFoundException e) { try { initializeJavaTextNormalizer(); } catch (final ClassNotFoundException e2) { throw new EncryptionInitializationException( "Cannot find a valid UNICODE normalizer: neither " + JDK_NORMALIZER_CLASS_NAME + " nor " + ICU_NORMALIZER_CLASS_NAME + " have been found at the classpath. If you are using " + "a version of the JDK older than JavaSE 6, you should include the icu4j library in " + "your classpath."); } catch (final NoSuchMethodException e2) { throw new EncryptionInitializationException( "Cannot find a valid UNICODE normalizer: " + JDK_NORMALIZER_CLASS_NAME + " has " + "been found at the classpath, but has an incompatible signature for its 'normalize' " + "method."); } catch (final NoSuchFieldException e2) { throw new EncryptionInitializationException( "Cannot find a valid UNICODE normalizer: " + JDK_NORMALIZER_FORM_CLASS_NAME + " has " + "been found at the classpath, but seems to have no 'NFC' value."); } catch (final IllegalAccessException e2) { throw new EncryptionInitializationException( "Cannot find a valid UNICODE normalizer: " + JDK_NORMALIZER_FORM_CLASS_NAME + " has " + "been found at the classpath, but seems to have no 'NFC' value."); } } } if (useIcuNormalizer.booleanValue()) { return normalizeWithIcu4j(message); } return normalizeWithJavaNormalizer(message); } static void initializeIcu4j() throws ClassNotFoundException { Thread.currentThread().getContextClassLoader().loadClass(ICU_NORMALIZER_CLASS_NAME); useIcuNormalizer = Boolean.TRUE; } static void initializeJavaTextNormalizer() throws ClassNotFoundException, NoSuchMethodException, NoSuchFieldException, IllegalAccessException { final Class javaTextNormalizerClass = Thread.currentThread().getContextClassLoader().loadClass(JDK_NORMALIZER_CLASS_NAME); final Class javaTextNormalizerFormClass = Thread.currentThread().getContextClassLoader().loadClass(JDK_NORMALIZER_FORM_CLASS_NAME); javaTextNormalizerMethod = javaTextNormalizerClass.getMethod( "normalize", new Class[]{ CharSequence.class, javaTextNormalizerFormClass }); final Field javaTextNormalizerFormNFCConstantField = javaTextNormalizerFormClass.getField("NFC"); javaTextNormalizerFormNFCConstant = javaTextNormalizerFormNFCConstantField.get(null); useIcuNormalizer = Boolean.FALSE; } static char[] normalizeWithJavaNormalizer(final char[] message) { if (javaTextNormalizerMethod == null || javaTextNormalizerFormNFCConstant == null) { throw new EncryptionInitializationException( "Cannot use: " + JDK_NORMALIZER_FORM_CLASS_NAME + ", as JDK-based normalization has " + "not been initialized! (check previous execution errors)"); } // Using java JDK's Normalizer, we cannot avoid creating Strings // (it is the only possible interface to the Normalizer class). // // Note java.text.Normalizer is accessed via reflection in order to allow this // class to be JDK 1.4-compilable (though ICU4j will be needed at runtime // if Java 1.4 is used). final String messageStr = new String(message); final String result; try { result = (String) javaTextNormalizerMethod.invoke( null, new Object[] { messageStr, javaTextNormalizerFormNFCConstant }); } catch (final Exception e) { throw new EncryptionInitializationException( "Could not perform a valid UNICODE normalization", e); } return result.toCharArray(); } static char[] normalizeWithIcu4j(final char[] message) { // initialize the result to twice the size of the message // this should be more than enough in most cases char[] normalizationResult = new char[message.length * 2]; int normalizationResultSize = 0; while(true) { // Execute normalization. The result will be written into the normalizationResult // char array, and the returned int will be the real size of the result. Normally, // this will be smaller than the size of normalizationResult, but if it is bigger, // we will have to create a new normalizationResult array and try again (icu4j will // not raise an exception, only return a value bigger than the destination array size). normalizationResultSize = com.ibm.icu.text.Normalizer.normalize(message, normalizationResult, com.ibm.icu.text.Normalizer.NFC, 0); if (normalizationResultSize <= normalizationResult.length) { // everything went OK and result fitted. Copy to a correctly-sized array // and clean normalizationResult final char[] result = new char[normalizationResultSize]; System.arraycopy(normalizationResult, 0, result, 0, normalizationResultSize); for (int i = 0; i < normalizationResult.length; i++) { normalizationResult[i] = (char)0; } return result; } // We need a bigger array. the old array must be cleaned also for (int i = 0; i < normalizationResult.length; i++) { normalizationResult[i] = (char)0; } normalizationResult = new char[normalizationResultSize]; } } private Normalizer() { super(); } }




© 2015 - 2024 Weber Informatics LLC | Privacy Policy