OpenSearch/src/main/java/org/elasticsearch/ExceptionsHelper.java

/*
 * Licensed to ElasticSearch and Shay Banon under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. ElasticSearch 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.elasticsearch;

import org.elasticsearch.common.logging.ESLogger;
import org.elasticsearch.common.logging.Loggers;

/**
 *
 */
public final class ExceptionsHelper {

    private static final ESLogger logger = Loggers.getLogger(ExceptionsHelper.class);

    public static Throwable unwrapCause(Throwable t) {
        int counter = 0;
        Throwable result = t;
        while (result instanceof ElasticSearchWrapperException) {
            if (result.getCause() == null) {
                return result;
            }
            if (result.getCause() == result) {
                return result;
            }
            if (counter++ > 10) {
                // dear god, if we got more than 10 levels down, WTF? just bail
                logger.warn("Exception cause unwrapping ran for 10 levels...", t);
                return result;
            }
            result = result.getCause();
        }
        return result;
    }

    public static String detailedMessage(Throwable t) {
        return detailedMessage(t, false, 0);
    }

    public static String detailedMessage(Throwable t, boolean newLines, int initialCounter) {
        if (t == null) {
            return "Unknown";
        }
        int counter = initialCounter + 1;
        if (t.getCause() != null) {
            StringBuilder sb = new StringBuilder();
            while (t != null) {
                if (t.getMessage() != null) {
                    sb.append(t.getClass().getSimpleName()).append("[");
                    sb.append(t.getMessage());
                    sb.append("]");
                    if (!newLines) {
                        sb.append("; ");
                    }
                }
                t = t.getCause();
                if (t != null) {
                    if (newLines) {
                        sb.append("\n");
                        for (int i = 0; i < counter; i++) {
                            sb.append("\t");
                        }
                    } else {
                        sb.append("nested: ");
                    }
                }
                counter++;
            }
            return sb.toString();
        } else {
            return t.getClass().getSimpleName() + "[" + t.getMessage() + "]";
        }
    }
}