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Maya Nlp subproject :mynlp
/*
* Copyright 2018 mayabot.com authors. 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.
* 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.mayabot.nlp.logging;
import java.text.MessageFormat;
import java.util.HashSet;
import java.util.Set;
// 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.
*/
final class MessageFormatter {
private 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
*/
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 argA The argument to be substituted in place of the first formatting
* anchor
* @param argB The argument to be substituted in place of the second formatting
* anchor
* @return The formatted message
*/
static FormattingTuple format(final String messagePattern,
Object argA, Object argB) {
return arrayFormat(messagePattern, new Object[]{argA, argB});
}
/**
* Same principle as the {@link #format(String, Object)} and
* {@link #format(String, Object, Object)} methods except that any number of
* arguments can be passed in an array.
*
* @param messagePattern The message pattern which will be parsed and formatted
* @param argArray An array of arguments to be substituted in place of formatting
* anchors
* @return The formatted message
*/
static FormattingTuple arrayFormat(final String messagePattern,
final Object[] argArray) {
if (argArray == null || argArray.length == 0) {
return new FormattingTuple(messagePattern, null);
}
int lastArrIdx = argArray.length - 1;
Object lastEntry = argArray[lastArrIdx];
Throwable throwable = lastEntry instanceof Throwable ? (Throwable) lastEntry : null;
if (messagePattern == null) {
return new FormattingTuple(null, throwable);
}
int j = messagePattern.indexOf(DELIM_STR);
if (j == -1) {
// this is a simple string
return new FormattingTuple(messagePattern, throwable);
}
StringBuilder sbuf = new StringBuilder(messagePattern.length() + 50);
int i = 0;
int L = 0;
do {
boolean notEscaped = j == 0 || messagePattern.charAt(j - 1) != ESCAPE_CHAR;
if (notEscaped) {
// normal case
sbuf.append(messagePattern, i, j);
} else {
sbuf.append(messagePattern, i, j - 1);
// check that escape char is not is escaped: "abc x:\\{}"
notEscaped = j >= 2 && messagePattern.charAt(j - 2) == ESCAPE_CHAR;
}
i = j + 2;
if (notEscaped) {
deeplyAppendParameter(sbuf, argArray[L], null);
L++;
if (L > lastArrIdx) {
break;
}
} else {
sbuf.append(DELIM_STR);
}
j = messagePattern.indexOf(DELIM_STR, i);
} while (j != -1);
// append the characters following the last {} pair.
sbuf.append(messagePattern, i, messagePattern.length());
return new FormattingTuple(sbuf.toString(), L <= lastArrIdx ? throwable : null);
}
// special treatment of array values was suggested by 'lizongbo'
private static void deeplyAppendParameter(StringBuilder sbuf, Object o,
Set seenSet) {
if (o == null) {
sbuf.append("null");
return;
}
Class objClass = o.getClass();
if (!objClass.isArray()) {
if (Number.class.isAssignableFrom(objClass)) {
// Prevent String instantiation for some number types
if (objClass == Long.class) {
sbuf.append(((Long) o).longValue());
} else if (objClass == Integer.class || objClass == Short.class || objClass == Byte.class) {
sbuf.append(((Number) o).intValue());
} else if (objClass == Double.class) {
sbuf.append(((Double) o).doubleValue());
} else if (objClass == Float.class) {
sbuf.append(((Float) o).floatValue());
} else {
safeObjectAppend(sbuf, o);
}
} else {
safeObjectAppend(sbuf, o);
}
} else {
// check for primitive array types because they
// unfortunately cannot be cast to Object[]
sbuf.append('[');
if (objClass == boolean[].class) {
booleanArrayAppend(sbuf, (boolean[]) o);
} else if (objClass == byte[].class) {
byteArrayAppend(sbuf, (byte[]) o);
} else if (objClass == char[].class) {
charArrayAppend(sbuf, (char[]) o);
} else if (objClass == short[].class) {
shortArrayAppend(sbuf, (short[]) o);
} else if (objClass == int[].class) {
intArrayAppend(sbuf, (int[]) o);
} else if (objClass == long[].class) {
longArrayAppend(sbuf, (long[]) o);
} else if (objClass == float[].class) {
floatArrayAppend(sbuf, (float[]) o);
} else if (objClass == double[].class) {
doubleArrayAppend(sbuf, (double[]) o);
} else {
objectArrayAppend(sbuf, (Object[]) o, seenSet);
}
sbuf.append(']');
}
}
private static void safeObjectAppend(StringBuilder sbuf, Object o) {
try {
String oAsString = o.toString();
sbuf.append(oAsString);
} catch (Throwable t) {
System.err
.println("SLF4J: Failed toString() invocation on an object of type ["
+ o.getClass().getName() + ']');
t.printStackTrace();
sbuf.append("[FAILED toString()]");
}
}
private static void objectArrayAppend(StringBuilder sbuf, Object[] a, Set seenSet) {
if (a.length == 0) {
return;
}
if (seenSet == null) {
seenSet = new HashSet(a.length);
}
if (seenSet.add(a)) {
deeplyAppendParameter(sbuf, a[0], seenSet);
for (int i = 1; i < a.length; i++) {
sbuf.append(", ");
deeplyAppendParameter(sbuf, a[i], seenSet);
}
// allow repeats in siblings
seenSet.remove(a);
} else {
sbuf.append("...");
}
}
private static void booleanArrayAppend(StringBuilder sbuf, boolean[] a) {
if (a.length == 0) {
return;
}
sbuf.append(a[0]);
for (int i = 1; i < a.length; i++) {
sbuf.append(", ");
sbuf.append(a[i]);
}
}
private static void byteArrayAppend(StringBuilder sbuf, byte[] a) {
if (a.length == 0) {
return;
}
sbuf.append(a[0]);
for (int i = 1; i < a.length; i++) {
sbuf.append(", ");
sbuf.append(a[i]);
}
}
private static void charArrayAppend(StringBuilder sbuf, char[] a) {
if (a.length == 0) {
return;
}
sbuf.append(a[0]);
for (int i = 1; i < a.length; i++) {
sbuf.append(", ");
sbuf.append(a[i]);
}
}
private static void shortArrayAppend(StringBuilder sbuf, short[] a) {
if (a.length == 0) {
return;
}
sbuf.append(a[0]);
for (int i = 1; i < a.length; i++) {
sbuf.append(", ");
sbuf.append(a[i]);
}
}
private static void intArrayAppend(StringBuilder sbuf, int[] a) {
if (a.length == 0) {
return;
}
sbuf.append(a[0]);
for (int i = 1; i < a.length; i++) {
sbuf.append(", ");
sbuf.append(a[i]);
}
}
private static void longArrayAppend(StringBuilder sbuf, long[] a) {
if (a.length == 0) {
return;
}
sbuf.append(a[0]);
for (int i = 1; i < a.length; i++) {
sbuf.append(", ");
sbuf.append(a[i]);
}
}
private static void floatArrayAppend(StringBuilder sbuf, float[] a) {
if (a.length == 0) {
return;
}
sbuf.append(a[0]);
for (int i = 1; i < a.length; i++) {
sbuf.append(", ");
sbuf.append(a[i]);
}
}
private static void doubleArrayAppend(StringBuilder sbuf, double[] a) {
if (a.length == 0) {
return;
}
sbuf.append(a[0]);
for (int i = 1; i < a.length; i++) {
sbuf.append(", ");
sbuf.append(a[i]);
}
}
private MessageFormatter() {
}
}