    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      https://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017
    018package org.apache.commons.io.output;
    019
    020import java.io.File;
    021import java.io.IOException;
    022import java.io.OutputStream;
    023import java.io.RandomAccessFile;
    024import java.nio.file.StandardOpenOption;
    025
    026import org.apache.commons.io.build.AbstractOrigin;
    027import org.apache.commons.io.build.AbstractStreamBuilder;
    028
    029/**
    030 * An {@link OutputStream} that writes to a {@link RandomAccessFile}.
    031 *
    032 * @since 2.18.0
    033 */
    034public final class RandomAccessFileOutputStream extends OutputStream {
    035
    036    // @formatter:off
    037    /**
    038     * Builds a new {@link RandomAccessFileOutputStream}.
    039     * <p>
    040     * For example:
    041     * </p>
    042     * <pre>{@code
    043     * RandomAccessFileOutputStream s = RandomAccessFileOutputStream.builder()
    044     *   .setFile("myfile.txt")
    045     *   .setOpenOptions(StandardOpenOption.SYNC)
    046     *   .get();}
    047     * </pre>
    048     * <p>
    049     * The only super's aspect used is buffer size.
    050     * </p>
    051     *
    052     * @see #get()
    053     */
    054    // @formatter:on
    055    public static final class Builder extends AbstractStreamBuilder<RandomAccessFileOutputStream, Builder> {
    056
    057        /**
    058         * Use {@link RandomAccessFileOutputStream#builder()}.
    059         */
    060        private Builder() {
    061            setOpenOptions(StandardOpenOption.WRITE);
    062        }
    063
    064        /**
    065         * Builds a new {@link RandomAccessFileOutputStream}.
    066         * <p>
    067         * You must set an aspect that supports {@link RandomAccessFile} or {@link File}, otherwise, this method throws an exception. Only set one of
    068         * RandomAccessFile or an origin that can be converted to a File.
    069         * </p>
    070         * <p>
    071         * This builder uses the following aspects:
    072         * </p>
    073         * <ul>
    074         * <li>{@link RandomAccessFile} is the target aspect.</li>
    075         * <li>{@link File}</li>
    076         * <li>closeOnClose</li>
    077         * </ul>
    078         *
    079         * @return a new instance.
    080         * @throws IllegalStateException         if the {@code origin} is {@code null}.
    081         * @throws IllegalStateException         if both RandomAccessFile and origin are set.
    082         * @throws UnsupportedOperationException if the origin cannot be converted to a {@link RandomAccessFile}.
    083         * @throws IOException                   if an I/O error occurs converting to an {@link RandomAccessFile} using {@link #getRandomAccessFile()}.
    084         * @see AbstractOrigin#getFile()
    085         * @see #getUnchecked()
    086         */
    087        @Override
    088        public RandomAccessFileOutputStream get() throws IOException {
    089            return new RandomAccessFileOutputStream(this);
    090        }
    091
    092    }
    093
    094    /**
    095     * Constructs a new {@link Builder}.
    096     *
    097     * @return a new {@link Builder}.
    098     */
    099    public static Builder builder() {
    100        return new Builder();
    101    }
    102
    103    private final RandomAccessFile randomAccessFile;
    104
    105    private RandomAccessFileOutputStream(final Builder builder) throws IOException {
    106        this.randomAccessFile = builder.getRandomAccessFile();
    107    }
    108
    109    @Override
    110    public void close() throws IOException {
    111        this.randomAccessFile.close();
    112        super.close();
    113    }
    114
    115    @SuppressWarnings("resource")
    116    @Override
    117    public void flush() throws IOException {
    118        randomAccessFile.getChannel().force(true);
    119        super.flush();
    120    }
    121
    122    /**
    123     * Gets the underlying random access file.
    124     *
    125     * @return the underlying random access file.
    126     * @since 2.19.0
    127     */
    128    public RandomAccessFile getRandomAccessFile() {
    129        return randomAccessFile;
    130    }
    131
    132    @Override
    133    public void write(final int b) throws IOException {
    134        randomAccessFile.write(b);
    135    }
    136
    137}