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/*
* 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.core.layout;
import java.nio.charset.Charset;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.logging.log4j.core.Layout;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.config.Configuration;
import org.apache.logging.log4j.core.config.DefaultConfiguration;
import org.apache.logging.log4j.core.config.Node;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginBuilderAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginBuilderFactory;
import org.apache.logging.log4j.core.config.plugins.PluginConfiguration;
import org.apache.logging.log4j.core.config.plugins.PluginElement;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;
import org.apache.logging.log4j.core.pattern.LogEventPatternConverter;
import org.apache.logging.log4j.core.pattern.PatternFormatter;
import org.apache.logging.log4j.core.pattern.PatternParser;
import org.apache.logging.log4j.core.pattern.RegexReplacement;
import org.apache.logging.log4j.util.Strings;
/**
* A flexible layout configurable with pattern string.
*
* The goal of this class is to {@link org.apache.logging.log4j.core.Layout#toByteArray format} a {@link LogEvent} and
* return the results. The format of the result depends on the conversion pattern.
*
*
* The conversion pattern is closely related to the conversion pattern of the printf function in C. A conversion pattern
* is composed of literal text and format control expressions called conversion specifiers.
*
*
* See the Log4j Manual for details on the supported pattern converters.
*
*/
@Plugin(name = "PatternLayout", category = Node.CATEGORY, elementType = Layout.ELEMENT_TYPE, printObject = true)
public final class PatternLayout extends AbstractStringLayout {
/**
* Default pattern string for log output. Currently set to the string "%m%n" which just prints the
* application supplied message.
*/
public static final String DEFAULT_CONVERSION_PATTERN = "%m%n";
/**
* A conversion pattern equivalent to the TTCCCLayout. Current value is %r [%t] %p %c %x - %m%n.
*/
public static final String TTCC_CONVERSION_PATTERN = "%r [%t] %p %c %x - %m%n";
/**
* A simple pattern. Current value is %d [%t] %p %c - %m%n.
*/
public static final String SIMPLE_CONVERSION_PATTERN = "%d [%t] %p %c - %m%n";
/** Key to identify pattern converters. */
public static final String KEY = "Converter";
/**
* Conversion pattern.
*/
private final String conversionPattern;
private final PatternSelector patternSelector;
private final Serializer eventSerializer;
/**
* Constructs a EnhancedPatternLayout using the supplied conversion pattern.
*
* @param config The Configuration.
* @param replace The regular expression to match.
* @param eventPattern conversion pattern.
* @param patternSelector The PatternSelector.
* @param charset The character set.
* @param alwaysWriteExceptions Whether or not exceptions should always be handled in this pattern (if {@code true},
* exceptions will be written even if the pattern does not specify so).
* @param noConsoleNoAnsi
* If {@code "true"} (default) and {@link System#console()} is null, do not output ANSI escape codes
* @param headerPattern header conversion pattern.
* @param footerPattern footer conversion pattern.
*/
private PatternLayout(final Configuration config, final RegexReplacement replace, final String eventPattern,
final PatternSelector patternSelector, final Charset charset, final boolean alwaysWriteExceptions,
final boolean noConsoleNoAnsi, final String headerPattern, final String footerPattern) {
super(config, charset,
createSerializer(config, replace, headerPattern, null, patternSelector, alwaysWriteExceptions,
noConsoleNoAnsi),
createSerializer(config, replace, footerPattern, null, patternSelector, alwaysWriteExceptions,
noConsoleNoAnsi));
this.conversionPattern = eventPattern;
this.patternSelector = patternSelector;
this.eventSerializer = createSerializer(config, replace, eventPattern, DEFAULT_CONVERSION_PATTERN,
patternSelector, alwaysWriteExceptions, noConsoleNoAnsi);
}
public static Serializer createSerializer(final Configuration configuration, final RegexReplacement replace,
final String pattern, final String defaultPattern, final PatternSelector patternSelector,
final boolean alwaysWriteExceptions, final boolean noConsoleNoAnsi) {
if (Strings.isEmpty(pattern) && Strings.isEmpty(defaultPattern)) {
return null;
}
if (patternSelector == null) {
try {
final PatternParser parser = createPatternParser(configuration);
final List list = parser.parse(pattern == null ? defaultPattern : pattern,
alwaysWriteExceptions, noConsoleNoAnsi);
final PatternFormatter[] formatters = list.toArray(new PatternFormatter[0]);
return new PatternSerializer(formatters, replace);
} catch (final RuntimeException ex) {
throw new IllegalArgumentException("Cannot parse pattern '" + pattern + "'", ex);
}
}
return new PatternSelectorSerializer(patternSelector, replace);
}
/**
* Gets the conversion pattern.
*
* @return the conversion pattern.
*/
public String getConversionPattern() {
return conversionPattern;
}
/**
* Gets this PatternLayout's content format. Specified by:
*
* - Key: "structured" Value: "false"
* - Key: "formatType" Value: "conversion" (format uses the keywords supported by OptionConverter)
* - Key: "format" Value: provided "conversionPattern" param
*
*
* @return Map of content format keys supporting PatternLayout
*/
@Override
public Map getContentFormat() {
final Map result = new HashMap<>();
result.put("structured", "false");
result.put("formatType", "conversion");
result.put("format", conversionPattern);
return result;
}
/**
* Formats a logging event to a writer.
*
* @param event logging event to be formatted.
* @return The event formatted as a String.
*/
@Override
public String toSerializable(final LogEvent event) {
return eventSerializer.toSerializable(event);
}
@Override
public void encode(final LogEvent event, final ByteBufferDestination destination) {
if (!(eventSerializer instanceof Serializer2)) {
super.encode(event, destination);
return;
}
final StringBuilder text = toText((Serializer2) eventSerializer, event, getStringBuilder());
final Encoder encoder = getStringBuilderEncoder();
encoder.encode(text, destination);
}
/**
* Creates a text representation of the specified log event
* and writes it into the specified StringBuilder.
*
* Implementations are free to return a new StringBuilder if they can
* detect in advance that the specified StringBuilder is too small.
*/
private StringBuilder toText(final Serializer2 serializer, final LogEvent event,
final StringBuilder destination) {
return serializer.toSerializable(event, destination);
}
/**
* Creates a PatternParser.
* @param config The Configuration.
* @return The PatternParser.
*/
public static PatternParser createPatternParser(final Configuration config) {
if (config == null) {
return new PatternParser(config, KEY, LogEventPatternConverter.class);
}
PatternParser parser = config.getComponent(KEY);
if (parser == null) {
parser = new PatternParser(config, KEY, LogEventPatternConverter.class);
config.addComponent(KEY, parser);
parser = config.getComponent(KEY);
}
return parser;
}
@Override
public String toString() {
return patternSelector == null ? conversionPattern : patternSelector.toString();
}
/**
* Creates a pattern layout.
*
* @param pattern
* The pattern. If not specified, defaults to DEFAULT_CONVERSION_PATTERN.
* @param patternSelector
* Allows different patterns to be used based on some selection criteria.
* @param config
* The Configuration. Some Converters require access to the Interpolator.
* @param replace
* A Regex replacement String.
* @param charset
* The character set. The platform default is used if not specified.
* @param alwaysWriteExceptions
* If {@code "true"} (default) exceptions are always written even if the pattern contains no exception tokens.
* @param noConsoleNoAnsi
* If {@code "true"} (default is false) and {@link System#console()} is null, do not output ANSI escape codes
* @param headerPattern
* The footer to place at the top of the document, once.
* @param footerPattern
* The footer to place at the bottom of the document, once.
* @return The PatternLayout.
*/
@PluginFactory
public static PatternLayout createLayout(
@PluginAttribute(value = "pattern", defaultString = DEFAULT_CONVERSION_PATTERN) final String pattern,
@PluginElement("PatternSelector") final PatternSelector patternSelector,
@PluginConfiguration final Configuration config,
@PluginElement("Replace") final RegexReplacement replace,
// LOG4J2-783 use platform default by default, so do not specify defaultString for charset
@PluginAttribute(value = "charset") final Charset charset,
@PluginAttribute(value = "alwaysWriteExceptions", defaultBoolean = true) final boolean alwaysWriteExceptions,
@PluginAttribute(value = "noConsoleNoAnsi", defaultBoolean = false) final boolean noConsoleNoAnsi,
@PluginAttribute("header") final String headerPattern,
@PluginAttribute("footer") final String footerPattern) {
return newBuilder()
.withPattern(pattern)
.withPatternSelector(patternSelector)
.withConfiguration(config)
.withRegexReplacement(replace)
.withCharset(charset)
.withAlwaysWriteExceptions(alwaysWriteExceptions)
.withNoConsoleNoAnsi(noConsoleNoAnsi)
.withHeader(headerPattern)
.withFooter(footerPattern)
.build();
}
private static class PatternSerializer implements Serializer, Serializer2 {
private final PatternFormatter[] formatters;
private final RegexReplacement replace;
private PatternSerializer(final PatternFormatter[] formatters, final RegexReplacement replace) {
super();
this.formatters = formatters;
this.replace = replace;
}
@Override
public String toSerializable(final LogEvent event) {
return toSerializable(event, getStringBuilder()).toString();
}
@Override
public StringBuilder toSerializable(final LogEvent event, final StringBuilder buffer) {
final int len = formatters.length;
for (int i = 0; i < len; i++) {
formatters[i].format(event, buffer);
}
if (replace != null) { // creates temporary objects
String str = buffer.toString();
str = replace.format(str);
buffer.setLength(0);
buffer.append(str);
}
return buffer;
}
@Override
public String toString() {
final StringBuilder builder = new StringBuilder();
builder.append(super.toString());
builder.append("[formatters=");
builder.append(Arrays.toString(formatters));
builder.append(", replace=");
builder.append(replace);
builder.append("]");
return builder.toString();
}
}
private static class PatternSelectorSerializer implements Serializer, Serializer2 {
private final PatternSelector patternSelector;
private final RegexReplacement replace;
private PatternSelectorSerializer(final PatternSelector patternSelector, final RegexReplacement replace) {
super();
this.patternSelector = patternSelector;
this.replace = replace;
}
@Override
public String toSerializable(final LogEvent event) {
return toSerializable(event, getStringBuilder()).toString();
}
@Override
public StringBuilder toSerializable(final LogEvent event, final StringBuilder buffer) {
final PatternFormatter[] formatters = patternSelector.getFormatters(event);
final int len = formatters.length;
for (int i = 0; i < len; i++) {
formatters[i].format(event, buffer);
}
if (replace != null) { // creates temporary objects
String str = buffer.toString();
str = replace.format(str);
buffer.setLength(0);
buffer.append(str);
}
return buffer;
}
@Override
public String toString() {
final StringBuilder builder = new StringBuilder();
builder.append(super.toString());
builder.append("[patternSelector=");
builder.append(patternSelector);
builder.append(", replace=");
builder.append(replace);
builder.append("]");
return builder.toString();
}
}
/**
* Creates a PatternLayout using the default options. These options include using UTF-8, the default conversion
* pattern, exceptions being written, and with ANSI escape codes.
*
* @return the PatternLayout.
* @see #DEFAULT_CONVERSION_PATTERN Default conversion pattern
*/
public static PatternLayout createDefaultLayout() {
return newBuilder().build();
}
/**
* Creates a PatternLayout using the default options and the given configuration. These options include using UTF-8,
* the default conversion pattern, exceptions being written, and with ANSI escape codes.
*
* @param configuration The Configuration.
*
* @return the PatternLayout.
* @see #DEFAULT_CONVERSION_PATTERN Default conversion pattern
*/
public static PatternLayout createDefaultLayout(final Configuration configuration) {
return newBuilder().withConfiguration(configuration).build();
}
/**
* Creates a builder for a custom PatternLayout.
*
* @return a PatternLayout builder.
*/
@PluginBuilderFactory
public static Builder newBuilder() {
return new Builder();
}
/**
* Custom PatternLayout builder. Use the {@link PatternLayout#newBuilder() builder factory method} to create this.
*/
public static class Builder implements org.apache.logging.log4j.core.util.Builder {
@PluginBuilderAttribute
private String pattern = PatternLayout.DEFAULT_CONVERSION_PATTERN;
@PluginElement("PatternSelector")
private PatternSelector patternSelector = null;
@PluginConfiguration
private Configuration configuration = null;
@PluginElement("Replace")
private RegexReplacement regexReplacement = null;
// LOG4J2-783 use platform default by default
@PluginBuilderAttribute
private Charset charset = Charset.defaultCharset();
@PluginBuilderAttribute
private boolean alwaysWriteExceptions = true;
@PluginBuilderAttribute
private boolean noConsoleNoAnsi = false;
@PluginBuilderAttribute
private String header = null;
@PluginBuilderAttribute
private String footer = null;
private Builder() {
}
// TODO: move javadocs from PluginFactory to here
public Builder withPattern(final String pattern) {
this.pattern = pattern;
return this;
}
public Builder withPatternSelector(final PatternSelector patternSelector) {
this.patternSelector = patternSelector;
return this;
}
public Builder withConfiguration(final Configuration configuration) {
this.configuration = configuration;
return this;
}
public Builder withRegexReplacement(final RegexReplacement regexReplacement) {
this.regexReplacement = regexReplacement;
return this;
}
public Builder withCharset(final Charset charset) {
// LOG4J2-783 if null, use platform default by default
if (charset != null) {
this.charset = charset;
}
return this;
}
public Builder withAlwaysWriteExceptions(final boolean alwaysWriteExceptions) {
this.alwaysWriteExceptions = alwaysWriteExceptions;
return this;
}
public Builder withNoConsoleNoAnsi(final boolean noConsoleNoAnsi) {
this.noConsoleNoAnsi = noConsoleNoAnsi;
return this;
}
public Builder withHeader(final String header) {
this.header = header;
return this;
}
public Builder withFooter(final String footer) {
this.footer = footer;
return this;
}
@Override
public PatternLayout build() {
// fall back to DefaultConfiguration
if (configuration == null) {
configuration = new DefaultConfiguration();
}
return new PatternLayout(configuration, regexReplacement, pattern, patternSelector, charset,
alwaysWriteExceptions, noConsoleNoAnsi, header, footer);
}
}
}