// Path: layout/src/main/java/com/vlkan/log4j2/logstash/layout/util/Throwables.java
// public enum Throwables {;
// 
//     public static Throwable getRootCause(Throwable throwable) {
// 
//         // Keep a second pointer that slowly walks the causal chain. If the fast pointer ever catches
//         // the slower pointer, then there's a loop.
//         Throwable slowPointer = throwable;
//         boolean advanceSlowPointer = false;
// 
//         Throwable cause;
//         while ((cause = throwable.getCause()) != null) {
//             throwable = cause;
//             if (throwable == slowPointer) {
//                 throw new IllegalArgumentException("loop in causal chain", throwable);
//             }
//             if (advanceSlowPointer) {
//                 slowPointer = slowPointer.getCause();
//             }
//             advanceSlowPointer = !advanceSlowPointer; // only advance every other iteration
//         }
//         return throwable;
// 
//     }
// 
// }


import com.fasterxml.jackson.core.JsonGenerator;
import com.vlkan.log4j2.logstash.layout.util.Throwables;
import org.apache.commons.lang3.StringUtils;
import org.apache.logging.log4j.core.LogEvent;
import java.io.IOException;
/*
 * Copyright 2017-2020 Volkan Yazıcı
 *
 * 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 permits and
 * limitations under the License.
 */

package com.vlkan.log4j2.logstash.layout.resolver;



class ExceptionRootCauseResolver implements EventResolver {

    private static final ExceptionInternalResolverFactory INTERNAL_RESOLVER_FACTORY =
            new ExceptionInternalResolverFactory() {

                @Override
                EventResolver createClassNameResolver() {
                    return (logEvent, jsonGenerator) -> {
                        Throwable exception = logEvent.getThrown();
                        if (exception == null) {
                            jsonGenerator.writeNull();
                        } else {
// Path: layout/src/main/java/com/vlkan/log4j2/logstash/layout/util/Throwables.java
// public enum Throwables {;
// 
//     public static Throwable getRootCause(Throwable throwable) {
// 
//         // Keep a second pointer that slowly walks the causal chain. If the fast pointer ever catches
//         // the slower pointer, then there's a loop.
//         Throwable slowPointer = throwable;
//         boolean advanceSlowPointer = false;
// 
//         Throwable cause;
//         while ((cause = throwable.getCause()) != null) {
//             throwable = cause;
//             if (throwable == slowPointer) {
//                 throw new IllegalArgumentException("loop in causal chain", throwable);
//             }
//             if (advanceSlowPointer) {
//                 slowPointer = slowPointer.getCause();
//             }
//             advanceSlowPointer = !advanceSlowPointer; // only advance every other iteration
//         }
//         return throwable;
// 
//     }
// 
// }


// Path: layout/src/main/java/com/vlkan/log4j2/logstash/layout/resolver/ExceptionRootCauseResolver.java
import com.fasterxml.jackson.core.JsonGenerator;
import com.vlkan.log4j2.logstash.layout.util.Throwables;
import org.apache.commons.lang3.StringUtils;
import org.apache.logging.log4j.core.LogEvent;
import java.io.IOException;

/*
 * Copyright 2017-2020 Volkan Yazıcı
 *
 * 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 permits and
 * limitations under the License.
 */

package com.vlkan.log4j2.logstash.layout.resolver;



class ExceptionRootCauseResolver implements EventResolver {

    private static final ExceptionInternalResolverFactory INTERNAL_RESOLVER_FACTORY =
            new ExceptionInternalResolverFactory() {

                @Override
                EventResolver createClassNameResolver() {
                    return (logEvent, jsonGenerator) -> {
                        Throwable exception = logEvent.getThrown();
                        if (exception == null) {
                            jsonGenerator.writeNull();
                        } else {
                            Throwable rootCause = Throwables.getRootCause(exception);