surefire-api/src/main/java/org/apache/maven/surefire/api/util/internal/DumpFileUtils.java

package org.apache.maven.surefire.api.util.internal;

/*
 * 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.
 */

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.Writer;
import java.text.SimpleDateFormat;
import java.util.Date;

import static java.nio.charset.StandardCharsets.UTF_8;

/**
 * Dumps a text or exception in dump file.
 * Each call logs a date when it was written to the dump file.
 *
 * @author <a href="mailto:tibordigana@apache.org">Tibor Digana (tibor17)</a>
 * @since 2.20
 */
public final class DumpFileUtils
{
    private DumpFileUtils()
    {
        throw new IllegalStateException( "no instantiable constructor" );
    }

    /**
     * New dump file. Synchronized object appears in main memory and perfectly visible in other threads.
     *
     * @param reportsDir    only report directory
     * @param dumpFileName    dump file name
     */
    public static synchronized File newDumpFile( File reportsDir, String dumpFileName )
    {
        return new File( reportsDir, dumpFileName );
    }

    public static void dumpException( Throwable t, File dumpFile )
    {
        dumpException( t, null, dumpFile );
    }

    public static void dumpException( Throwable t, String msg, File dumpFile )
    {
        try
        {
            if ( t != null && dumpFile != null
                         && ( dumpFile.exists() || mkdirs( dumpFile ) && dumpFile.createNewFile() ) )
            {
                try ( PrintWriter pw = new PrintWriter( createWriter( dumpFile ) ) )
                {
                    if ( msg != null )
                    {
                        pw.append( msg )
                                .append( StringUtils.NL );
                    }
                    t.printStackTrace( pw );
                    pw.append( StringUtils.NL )
                      .append( StringUtils.NL );
                }
            }
        }
        catch ( Exception e )
        {
            // do nothing
        }
    }

    public static void dumpText( String msg, File dumpFile )
    {
        try
        {
            if ( msg != null && dumpFile != null
                         && ( dumpFile.exists() || mkdirs( dumpFile ) && dumpFile.createNewFile() ) )
            {
                try ( Writer writer = createWriter( dumpFile ) )
                {
                    writer.append( msg )
                            .append( StringUtils.NL )
                            .append( StringUtils.NL );
                }
            }
        }
        catch ( Exception e )
        {
            // do nothing
        }
    }

    public static String newFormattedDateFileName()
    {
        return new SimpleDateFormat( "yyyy-MM-dd'T'HH-mm-ss_SSS" ).format( new Date() );
    }

    private static Writer createWriter( File dumpFile ) throws IOException
    {
        return new OutputStreamWriter( new FileOutputStream( dumpFile, true ), UTF_8 )
                       .append( "# Created at " )
                       .append( new SimpleDateFormat( "yyyy-MM-dd'T'HH:mm:ss.SSS" ).format( new Date() ) )
                       .append( StringUtils.NL );
    }

    private static boolean mkdirs( File dumpFile )
    {
        File dir = dumpFile.getParentFile();
        return dir.exists() || dir.mkdirs();
    }
}