org.apache.logging.log4j.util.Chars Maven / Gradle / Ivy
/*
* 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 org.apache.logging.log4j.util;
/**
* Consider this class private.
*/
@InternalApi
public final class Chars {
/** Carriage Return. */
public static final char CR = '\r';
/** Double Quote. */
public static final char DQUOTE = '\"';
/** Equals '='. */
public static final char EQ = '=';
/** Line Feed. */
public static final char LF = '\n';
/** NUL. */
public static final char NUL = 0;
/** Single Quote [']. */
public static final char QUOTE = '\'';
/** Space. */
public static final char SPACE = ' ';
/** Tab. */
public static final char TAB = '\t';
/**
* Converts a digit into an upper-case hexadecimal character or the null character if invalid.
*
* @param digit a number 0 - 15
* @return the hex character for that digit or '\0' if invalid
*/
public static char getUpperCaseHex(final int digit) {
if (digit < 0 || digit >= 16) {
return '\0';
}
return digit < 10 ? getNumericalDigit(digit) : getUpperCaseAlphaDigit(digit);
}
/**
* Converts a digit into an lower-case hexadecimal character or the null character if invalid.
*
* @param digit a number 0 - 15
* @return the hex character for that digit or '\0' if invalid
*/
public static char getLowerCaseHex(final int digit) {
if (digit < 0 || digit >= 16) {
return '\0';
}
return digit < 10 ? getNumericalDigit(digit) : getLowerCaseAlphaDigit(digit);
}
private static char getNumericalDigit(final int digit) {
return (char) ('0' + digit);
}
private static char getUpperCaseAlphaDigit(final int digit) {
return (char) ('A' + digit - 10);
}
private static char getLowerCaseAlphaDigit(final int digit) {
return (char) ('a' + digit - 10);
}
private Chars() {}
}