org.schedulesdirect.api.exception.JsonEncodingException.java Source code

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Here is the source code for org.schedulesdirect.api.exception.JsonEncodingException.java

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/*
 *      Copyright 2014 Battams, Derek
 *       
 *       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 org.schedulesdirect.api.exception;

import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.text.SimpleDateFormat;
import java.util.Date;

import org.apache.commons.io.FileUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.schedulesdirect.api.Config;

/**
 * When String input is expected to be JSON encoded data, but isn't then this exception is thrown in response
 * @author Derek Battams <derek@battams.ca>
 *
 */
public class JsonEncodingException extends IOException {

    private static final long serialVersionUID = 1L;
    static private final Log LOG = LogFactory.getLog(JsonEncodingException.class);
    static private volatile boolean targetCleaned = false;

    private String src;

    /**
     * 
     * @param message The message to associate with the exception
     * @param src The input that caused the exception
     */
    public JsonEncodingException(String message, String src) {
        super(message);
        this.src = src;
        capture();
    }

    /**
     * 
     * @param cause The cause of the exception
     * @param src The input that caused the exception
     */
    public JsonEncodingException(Throwable cause, String src) {
        super(cause);
        this.src = src;
        capture();
    }

    /**
     * 
     * @param message The message to associate with the exception
     * @param cause The cause of the exception
     * @param src The input that caused the exception
     */
    public JsonEncodingException(String message, Throwable cause, String src) {
        super(message, cause);
        this.src = src;
        capture();
    }

    /**
     * Generate the capture file for this exception, if requested
     */
    protected void capture() {
        Config conf = Config.get();
        if (conf.captureJsonEncodingErrors()) {
            String msg = generateMsg();
            try {
                Path p = Paths.get(conf.captureRoot().getAbsolutePath(), "encode");
                if (!targetCleaned && Files.exists(p))
                    try {
                        FileUtils.deleteDirectory(p.toFile());
                    } catch (IOException e) {
                        LOG.warn(String.format("Unable to clean target dir! [%s]", p));
                    }
                targetCleaned = true;
                Files.createDirectories(p);
                Path f = Files.createTempFile(p, prefix(), ".err");
                Files.write(f, msg.getBytes("UTF-8"));
            } catch (IOException e) {
                LOG.error("Unable to write capture file, logging it instead!", e);
                LOG.error(String.format("Invalid JSON received!%n%s", msg), this);
            }
        }
    }

    private String prefix() {
        return String.format("%s_", new SimpleDateFormat("yyyyMMddHHmmss").format(new Date()));
    }

    private String generateMsg() {
        StringWriter sw = new StringWriter();
        sw.append(String.format("*** S T A C K  T R A C E ***%n"));
        try (PrintWriter pw = new PrintWriter(sw)) {
            printStackTrace(pw);
        }
        sw.append(String.format("%n*** I N P U T ***%n%s", src));
        return sw.toString();
    }
}