com.ksc.util.CodecUtils Maven / Gradle / Ivy
/*
* Copyright 2013-2016 ksyun.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://ksyun.com/apache2.0
*
* or in the "license" file accompanying this file. This file 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.ksc.util;
/**
* Codec internal utilities
*
* @author Hanson Char
*/
public enum CodecUtils {
;
/**
* Transforms the given string into the given destination byte array
* truncating each character into a byte and skipping carriage returns and
* line feeds if any.
*
* dmurray: "It so happens that we're currently only calling this method
* with src.length == dest.length, in which case it works, but we could
* theoretically get away with passing a smaller dest if we knew ahead of
* time that src contained some number of spaces. In that case it looks like
* this implementation would truncate the result."
*
* hchar:
* "Yes, but the truncation is the intentional behavior of this internal
* routine in that case."
*
* @param singleOctets
* non-null string containing only single octet characters
* @param dest
* destination byte array
*
* @return the actual length of the destination byte array holding data
* @throws IllegalArgumentException
* if the input string contains any multi-octet character
*/
static int sanitize(final String singleOctets, byte[] dest) {
final int capacity = dest.length;
final char[] src = singleOctets.toCharArray();
int limit=0;
for (int i=0; i < capacity; i++) {
final char c = src[i];
if (c == '\r' || c == '\n' || c == ' ')
continue;
if (c > Byte.MAX_VALUE)
throw new IllegalArgumentException("Invalid character found at position " + i + " for " + singleOctets);
dest[limit++] = (byte)c;
}
return limit;
}
/**
* Returns a byte array representing the given string,
* truncating each character into a byte directly.
*
* @throws IllegalArgumentException if the input string contains any multi-octet character
*/
public static byte[] toBytesDirect(final String singleOctets) {
final char[] src = singleOctets.toCharArray();
final byte[] dest = new byte[src.length];
for (int i=0; i < dest.length; i++) {
final char c = src[i];
if (c > Byte.MAX_VALUE)
throw new IllegalArgumentException("Invalid character found at position " + i + " for " + singleOctets);
dest[i] = (byte)c;
}
return dest;
}
/**
* Returns a string representing the given byte array,
* treating each byte as a single octet character.
*/
public static String toStringDirect(final byte[] bytes) {
final char[] dest = new char[bytes.length];
int i=0;
for (byte b: bytes)
dest[i++] = (char)b;
return new String(dest);
}
/**
* Sanity check the last decoded position is a possible value.
*
* @throws IllegalArgumentException if the given decoded position is
* not a possible value produced via the respective encoding
*/
static void sanityCheckLastPos(int pos, int mask) {
if ((pos & mask) != 0) {
throw new IllegalArgumentException
("Invalid last non-pad character detected");
}
}
}