IOUtils.java

/*
 * (C) Copyright 2006-2016 Nuxeo SA (http://nuxeo.com/) and others.
 *
 * 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.
 *
 * Contributors:
 *     bstefanescu
 */
package org.nuxeo.ecm.automation.client.jaxrs.util;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.Reader;

/**
 * File is deleted on JVM exit. You should delete it explicitly earlier if you know it won't be used anymore.
 *
 * @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a>
 */
public class IOUtils {

    private static final int BUFFER_SIZE = 1024 * 64; // 64K

    private static final int MAX_BUFFER_SIZE = 1024 * 1024; // 64K

    private static final int MIN_BUFFER_SIZE = 1024 * 8; // 64K

    private IOUtils() {
    }

    private static byte[] createBuffer(int preferredSize) {
        if (preferredSize < 1) {
            preferredSize = BUFFER_SIZE;
        }
        if (preferredSize > MAX_BUFFER_SIZE) {
            preferredSize = MAX_BUFFER_SIZE;
        } else if (preferredSize < MIN_BUFFER_SIZE) {
            preferredSize = MIN_BUFFER_SIZE;
        }
        return new byte[preferredSize];
    }

    public static void copy(InputStream in, OutputStream out) throws IOException {
        byte[] buffer = createBuffer(in.available());
        int read;
        while ((read = in.read(buffer)) != -1) {
            out.write(buffer, 0, read);
        }
    }

    public static File copyToTempFile(InputStream in) throws IOException {
        File file = File.createTempFile("nxautomation-", ".tmp", new File(System.getProperty("java.io.tmpdir")));
        file.deleteOnExit();
        copyToFile(in, file, true);
        return file;
    }

    public static File copyToTempFile(InputStream in, boolean closeIn) throws IOException {
        File file = File.createTempFile("nxautomation-", ".tmp", new File(System.getProperty("java.io.tmpdir")));
        file.deleteOnExit();
        copyToFile(in, file, closeIn);
        return file;
    }

    public static void copyToFile(InputStream in, File file) throws IOException {
        copyToFile(in, file, true);
    }

    public static void copyToFile(InputStream in, File file, boolean closeIn) throws IOException {
        FileOutputStream out = new FileOutputStream(file);
        try {
            copy(in, out);
        } finally {
            out.close();
            if (closeIn) {
                in.close();
            }
        }
    }

    public static void writeToFile(String content, File file) throws IOException {
        FileOutputStream out = new FileOutputStream(file);
        try {
            write(content, out);
        } finally {
            out.close();
        }
    }

    public static void write(String content, OutputStream out) throws IOException {
        out.write(content.getBytes());
    }

    public static String read(InputStream in) throws IOException {
        InputStreamReader reader = new InputStreamReader(in, "UTF-8");
        return read(reader);
    }

    public static String read(Reader in) throws IOException {
        StringBuilder sb = new StringBuilder();
        try {
            int read;
            char[] buffer = new char[64 * 1024];
            while ((read = in.read(buffer)) != -1) {
                sb.append(new String(buffer, 0, read));
            }
        } finally {
            in.close();
        }
        return sb.toString();
    }

}