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/**
* lines (18 sloc) 1.11 KB
* Copyright (c) 2004-2017 QOS.ch
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package io.webfolder.cdp.logger;
import java.text.MessageFormat;
import java.util.HashMap;
import java.util.Map;
// contributors: lizongbo: proposed special treatment of array parameter values
// Joern Huxhorn: pointed out double[] omission, suggested deep array copy
/**
* Formats messages according to very simple substitution rules. Substitutions
* can be made 1, 2 or more arguments.
*
*
* For example,
*
*
* MessageFormatter.format("Hi {}.", "there")
*
*
* will return the string "Hi there.".
*
* The {} pair is called the formatting anchor. It serves to designate
* the location where arguments need to be substituted within the message
* pattern.
*
* In case your message contains the '{' or the '}' character, you do not have
* to do anything special unless the '}' character immediately follows '{'. For
* example,
*
*
* MessageFormatter.format("Set {1,2,3} is not equal to {}.", "1,2");
*
*
* will return the string "Set {1,2,3} is not equal to 1,2.".
*
*
* If for whatever reason you need to place the string "{}" in the message
* without its formatting anchor meaning, then you need to escape the
* '{' character with '\', that is the backslash character. Only the '{'
* character should be escaped. There is no need to escape the '}' character.
* For example,
*
*
* MessageFormatter.format("Set \\{} is not equal to {}.", "1,2");
*
*
* will return the string "Set {} is not equal to 1,2.".
*
*
* The escaping behavior just described can be overridden by escaping the escape
* character '\'. Calling
*
*
* MessageFormatter.format("File name is C:\\\\{}.", "file.zip");
*
*
* will return the string "File name is C:\file.zip".
*
*
* The formatting conventions are different than those of {@link MessageFormat}
* which ships with the Java platform. This is justified by the fact that
* SLF4J's implementation is 10 times faster than that of {@link MessageFormat}.
* This local performance difference is both measurable and significant in the
* larger context of the complete logging processing chain.
*
*
* See also {@link #format(String, Object)},
* {@link #format(String, Object, Object)} and
* {@link #arrayFormat(String, Object[])} methods for more details.
*
* @author Ceki Gülcü
* @author Joern Huxhorn
*/
class MessageFormatter {
static final char DELIM_START = '{';
static final char DELIM_STOP = '}';
static final String DELIM_STR = "{}";
private static final char ESCAPE_CHAR = '\\';
/**
* Performs single argument substitution for the 'messagePattern' passed as
* parameter.
*
* For example,
*
*
* MessageFormatter.format("Hi {}.", "there");
*
*
* will return the string "Hi there.".
*
*
* @param messagePattern
* The message pattern which will be parsed and formatted
* @param arg
* The argument to be substituted in place of the formatting anchor
* @return The formatted message
*/
final public static FormattingTuple format(String messagePattern, Object arg) {
return arrayFormat(messagePattern, new Object[] { arg });
}
/**
*
* Performs a two argument substitution for the 'messagePattern' passed as
* parameter.
*
* For example,
*
*
* MessageFormatter.format("Hi {}. My name is {}.", "Alice", "Bob");
*
*
* will return the string "Hi Alice. My name is Bob.".
*
* @param messagePattern
* The message pattern which will be parsed and formatted
* @param arg1
* The argument to be substituted in place of the first formatting
* anchor
* @param arg2
* The argument to be substituted in place of the second formatting
* anchor
* @return The formatted message
*/
final public static FormattingTuple format(final String messagePattern, Object arg1, Object arg2) {
return arrayFormat(messagePattern, new Object[] { arg1, arg2 });
}
static final Throwable getThrowableCandidate(Object[] argArray) {
if (argArray == null || argArray.length == 0) {
return null;
}
final Object lastEntry = argArray[argArray.length - 1];
if (lastEntry instanceof Throwable) {
return (Throwable) lastEntry;
}
return null;
}
final public static FormattingTuple arrayFormat(final String messagePattern, final Object[] argArray) {
Throwable throwableCandidate = getThrowableCandidate(argArray);
Object[] args = argArray;
if (throwableCandidate != null) {
args = trimmedCopy(argArray);
}
return arrayFormat(messagePattern, args, throwableCandidate);
}
private static Object[] trimmedCopy(Object[] argArray) {
if (argArray == null || argArray.length == 0) {
throw new IllegalStateException("non-sensical empty or null argument array");
}
final int trimemdLen = argArray.length - 1;
Object[] trimmed = new Object[trimemdLen];
System.arraycopy(argArray, 0, trimmed, 0, trimemdLen);
return trimmed;
}
final public static FormattingTuple arrayFormat(final String messagePattern, final Object[] argArray, Throwable throwable) {
if (messagePattern == null) {
return new FormattingTuple(null, argArray, throwable);
}
if (argArray == null) {
return new FormattingTuple(messagePattern);
}
int i = 0;
int j;
// use string builder for better multicore performance
StringBuilder sbuf = new StringBuilder(messagePattern.length() + 50);
int L;
for (L = 0; L < argArray.length; L++) {
j = messagePattern.indexOf(DELIM_STR, i);
if (j == -1) {
// no more variables
if (i == 0) { // this is a simple string
return new FormattingTuple(messagePattern, argArray, throwable);
} else { // add the tail string which contains no variables and return
// the result.
sbuf.append(messagePattern, i, messagePattern.length());
return new FormattingTuple(sbuf.toString(), argArray, throwable);
}
} else {
if (isEscapedDelimeter(messagePattern, j)) {
if (!isDoubleEscaped(messagePattern, j)) {
L--; // DELIM_START was escaped, thus should not be incremented
sbuf.append(messagePattern, i, j - 1);
sbuf.append(DELIM_START);
i = j + 1;
} else {
// The escape character preceding the delimiter start is
// itself escaped: "abc x:\\{}"
// we have to consume one backward slash
sbuf.append(messagePattern, i, j - 1);
deeplyAppendParameter(sbuf, argArray[L], new HashMap