/* * 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. */ package com.hotent.system.encode; import java.io.UnsupportedEncodingException; import java.nio.charset.Charset; /** * Converts String to and from bytes using the encodings required by the Java specification. These encodings are * specified in * Standard charsets. * *
This class is immutable and thread-safe.
* * @see CharEncoding * @see Standard charsets * @version $Id: StringUtils.java 1435550 2013-01-19 14:09:52Z tn $ * @since 1.4 */ public class StringUtils { /** * Calls {@link String#getBytes(Charset)} * * @param string * The string to encode (if null, return null). * @param charset * The {@link Charset} to encode the {@code String} * @return the encoded bytes */ private static byte[] getBytes(final String string, final Charset charset) { if (string == null) { return null; } return string.getBytes(charset); } /** * Encodes the given string into a sequence of bytes using the ISO-8859-1 charset, storing the result into a new * byte array. * * @param string * the String to encode, may be {@code null} * @return encoded bytes, or {@code null} if the input string was {@code null} * @throws NullPointerException * Thrown if {@link Charsets#ISO_8859_1} is not initialized, which should never happen since it is * required by the Java platform specification. * @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException * @see Standard charsets * @see #getBytesUnchecked(String, String) */ public static byte[] getBytesIso8859_1(final String string) { return getBytes(string, Charsets.ISO_8859_1); } /** * Encodes the given string into a sequence of bytes using the named charset, storing the result into a new byte * array. ** This method catches {@link UnsupportedEncodingException} and rethrows it as {@link IllegalStateException}, which * should never happen for a required charset name. Use this method when the encoding is required to be in the JRE. *
* * @param string * the String to encode, may be {@code null} * @param charsetName * The name of a required {@link Charset} * @return encoded bytes, or {@code null} if the input string was {@code null} * @throws IllegalStateException * Thrown when a {@link UnsupportedEncodingException} is caught, which should never happen for a * required charset name. * @see CharEncoding * @see String#getBytes(String) */ public static byte[] getBytesUnchecked(final String string, final String charsetName) { if (string == null) { return null; } try { return string.getBytes(charsetName); } catch (final UnsupportedEncodingException e) { throw StringUtils.newIllegalStateException(charsetName, e); } } /** * Encodes the given string into a sequence of bytes using the US-ASCII charset, storing the result into a new byte * array. * * @param string * the String to encode, may be {@code null} * @return encoded bytes, or {@code null} if the input string was {@code null} * @throws NullPointerException * Thrown if {@link Charsets#US_ASCII} is not initialized, which should never happen since it is * required by the Java platform specification. * @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException * @see Standard charsets * @see #getBytesUnchecked(String, String) */ public static byte[] getBytesUsAscii(final String string) { return getBytes(string, Charsets.US_ASCII); } /** * Encodes the given string into a sequence of bytes using the UTF-16 charset, storing the result into a new byte * array. * * @param string * the String to encode, may be {@code null} * @return encoded bytes, or {@code null} if the input string was {@code null} * @throws NullPointerException * Thrown if {@link Charsets#UTF_16} is not initialized, which should never happen since it is * required by the Java platform specification. * @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException * @see Standard charsets * @see #getBytesUnchecked(String, String) */ public static byte[] getBytesUtf16(final String string) { return getBytes(string, Charsets.UTF_16); } /** * Encodes the given string into a sequence of bytes using the UTF-16BE charset, storing the result into a new byte * array. * * @param string * the String to encode, may be {@code null} * @return encoded bytes, or {@code null} if the input string was {@code null} * @throws NullPointerException * Thrown if {@link Charsets#UTF_16BE} is not initialized, which should never happen since it is * required by the Java platform specification. * @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException * @see Standard charsets * @see #getBytesUnchecked(String, String) */ public static byte[] getBytesUtf16Be(final String string) { return getBytes(string, Charsets.UTF_16BE); } /** * Encodes the given string into a sequence of bytes using the UTF-16LE charset, storing the result into a new byte * array. * * @param string * the String to encode, may be {@code null} * @return encoded bytes, or {@code null} if the input string was {@code null} * @throws NullPointerException * Thrown if {@link Charsets#UTF_16LE} is not initialized, which should never happen since it is * required by the Java platform specification. * @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException * @see Standard charsets * @see #getBytesUnchecked(String, String) */ public static byte[] getBytesUtf16Le(final String string) { return getBytes(string, Charsets.UTF_16LE); } /** * Encodes the given string into a sequence of bytes using the UTF-8 charset, storing the result into a new byte * array. * * @param string * the String to encode, may be {@code null} * @return encoded bytes, or {@code null} if the input string was {@code null} * @throws NullPointerException * Thrown if {@link Charsets#UTF_8} is not initialized, which should never happen since it is * required by the Java platform specification. * @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException * @see Standard charsets * @see #getBytesUnchecked(String, String) */ public static byte[] getBytesUtf8(final String string) { return getBytes(string, Charsets.UTF_8); } private static IllegalStateException newIllegalStateException(final String charsetName, final UnsupportedEncodingException e) { return new IllegalStateException(charsetName + ": " + e); } /** * Constructs a newString
by decoding the specified array of bytes using the given charset.
*
* @param bytes
* The bytes to be decoded into characters
* @param charset
* The {@link Charset} to encode the {@code String}
* @return A new String
decoded from the specified array of bytes using the given charset,
* or {@code null} if the input byte array was {@code null}.
* @throws NullPointerException
* Thrown if {@link Charsets#UTF_8} is not initialized, which should never happen since it is
* required by the Java platform specification.
*/
private static String newString(final byte[] bytes, final Charset charset) {
return bytes == null ? null : new String(bytes, charset);
}
/**
* Constructs a new String
by decoding the specified array of bytes using the given charset.
* * This method catches {@link UnsupportedEncodingException} and re-throws it as {@link IllegalStateException}, which * should never happen for a required charset name. Use this method when the encoding is required to be in the JRE. *
* * @param bytes * The bytes to be decoded into characters, may be {@code null} * @param charsetName * The name of a required {@link Charset} * @return A newString
decoded from the specified array of bytes using the given charset,
* or {@code null} if the input byte array was {@code null}.
* @throws IllegalStateException
* Thrown when a {@link UnsupportedEncodingException} is caught, which should never happen for a
* required charset name.
* @see CharEncoding
* @see String#String(byte[], String)
*/
public static String newString(final byte[] bytes, final String charsetName) {
if (bytes == null) {
return null;
}
try {
return new String(bytes, charsetName);
} catch (final UnsupportedEncodingException e) {
throw StringUtils.newIllegalStateException(charsetName, e);
}
}
/**
* Constructs a new String
by decoding the specified array of bytes using the ISO-8859-1 charset.
*
* @param bytes
* The bytes to be decoded into characters, may be {@code null}
* @return A new String
decoded from the specified array of bytes using the ISO-8859-1 charset, or
* {@code null} if the input byte array was {@code null}.
* @throws NullPointerException
* Thrown if {@link Charsets#ISO_8859_1} is not initialized, which should never happen since it is
* required by the Java platform specification.
* @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException
*/
public static String newStringIso8859_1(final byte[] bytes) {
return new String(bytes, Charsets.ISO_8859_1);
}
/**
* Constructs a new String
by decoding the specified array of bytes using the US-ASCII charset.
*
* @param bytes
* The bytes to be decoded into characters
* @return A new String
decoded from the specified array of bytes using the US-ASCII charset,
* or {@code null} if the input byte array was {@code null}.
* @throws NullPointerException
* Thrown if {@link Charsets#US_ASCII} is not initialized, which should never happen since it is
* required by the Java platform specification.
* @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException
*/
public static String newStringUsAscii(final byte[] bytes) {
return new String(bytes, Charsets.US_ASCII);
}
/**
* Constructs a new String
by decoding the specified array of bytes using the UTF-16 charset.
*
* @param bytes
* The bytes to be decoded into characters
* @return A new String
decoded from the specified array of bytes using the UTF-16 charset
* or {@code null} if the input byte array was {@code null}.
* @throws NullPointerException
* Thrown if {@link Charsets#UTF_16} is not initialized, which should never happen since it is
* required by the Java platform specification.
* @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException
*/
public static String newStringUtf16(final byte[] bytes) {
return new String(bytes, Charsets.UTF_16);
}
/**
* Constructs a new String
by decoding the specified array of bytes using the UTF-16BE charset.
*
* @param bytes
* The bytes to be decoded into characters
* @return A new String
decoded from the specified array of bytes using the UTF-16BE charset,
* or {@code null} if the input byte array was {@code null}.
* @throws NullPointerException
* Thrown if {@link Charsets#UTF_16BE} is not initialized, which should never happen since it is
* required by the Java platform specification.
* @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException
*/
public static String newStringUtf16Be(final byte[] bytes) {
return new String(bytes, Charsets.UTF_16BE);
}
/**
* Constructs a new String
by decoding the specified array of bytes using the UTF-16LE charset.
*
* @param bytes
* The bytes to be decoded into characters
* @return A new String
decoded from the specified array of bytes using the UTF-16LE charset,
* or {@code null} if the input byte array was {@code null}.
* @throws NullPointerException
* Thrown if {@link Charsets#UTF_16LE} is not initialized, which should never happen since it is
* required by the Java platform specification.
* @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException
*/
public static String newStringUtf16Le(final byte[] bytes) {
return new String(bytes, Charsets.UTF_16LE);
}
/**
* Constructs a new String
by decoding the specified array of bytes using the UTF-8 charset.
*
* @param bytes
* The bytes to be decoded into characters
* @return A new String
decoded from the specified array of bytes using the UTF-8 charset,
* or {@code null} if the input byte array was {@code null}.
* @throws NullPointerException
* Thrown if {@link Charsets#UTF_8} is not initialized, which should never happen since it is
* required by the Java platform specification.
* @since As of 1.7, throws {@link NullPointerException} instead of UnsupportedEncodingException
*/
public static String newStringUtf8(final byte[] bytes) {
return newString(bytes, Charsets.UTF_8);
}
}