com.aliyun.openservices.eas.discovery.utils.IOUtils Maven / Gradle / Ivy

package com.aliyun.openservices.eas.discovery.utils;

import com.aliyun.openservices.eas.discovery.core.DiscoveryClient;

import java.io.*;
import java.nio.channels.FileChannel;
import java.util.ArrayList;
import java.util.List;
import java.util.zip.GZIPInputStream;


public class IOUtils {

    static public String toString(InputStream input, String encoding) throws IOException {
        return (null == encoding) ? toString(new InputStreamReader(input))
                : toString(new InputStreamReader(input, encoding));
    }

    static public String toString(Reader reader) throws IOException {
        CharArrayWriter sw = new CharArrayWriter();
        copy(reader, sw);
        return sw.toString();
    }

    static public long copy(Reader input, Writer output) throws IOException {
        char[] buffer = new char[1 << 12];
        long count = 0;
        for (int n = 0; (n = input.read(buffer)) >= 0; ) {
            output.write(buffer, 0, n);
            count += n;
        }
        return count;
    }

    static public long copy(InputStream input, OutputStream output) throws IOException {
        byte[] buffer = new byte[1024]; // Adjust if you want
        int bytesRead;
        int totalBytes = 0;
        while ((bytesRead = input.read(buffer)) != -1) {
            output.write(buffer, 0, bytesRead);

            totalBytes += bytesRead;
        }

        return totalBytes;
    }


    static public List readLines(Reader input) throws IOException {
        BufferedReader reader = toBufferedReader(input);
        List list = new ArrayList();
        String line = null;
        for (; ; ) {
            line = reader.readLine();
            if (null != line) {
                list.add(line);
            } else {
                break;
            }
        }
        return list;
    }

    static private BufferedReader toBufferedReader(Reader reader) {
        return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(
                reader);
    }


    static public void copyFile(String source, String target) throws IOException {
        File sf = new File(source);
        if (!sf.exists()) {
            throw new IllegalArgumentException("source file does not exist.");
        }
        File tf = new File(target);
        tf.getParentFile().mkdirs();
        if (!tf.exists() && !tf.createNewFile()) {
            throw new RuntimeException("failed to create target file.");
        }

        FileChannel sc = null;
        FileChannel tc = null;
        try {
            tc = new FileOutputStream(tf).getChannel();
            sc = new FileInputStream(sf).getChannel();
            sc.transferTo(0, sc.size(), tc);
        } finally {
            if (null != sc) {
                sc.close();
            }
            if (null != tc) {
                tc.close();
            }
        }
    }

    public static void delete(File fileOrDir) throws IOException {
        if (fileOrDir == null) {
            return;
        }

        if (fileOrDir.isDirectory()) {
            cleanDirectory(fileOrDir);
        }

        fileOrDir.delete();
    }

    public static void cleanDirectory(File directory) throws IOException {
        if (!directory.exists()) {
            String message = directory + " does not exist";
            throw new IllegalArgumentException(message);
        }

        if (!directory.isDirectory()) {
            String message = directory + " is not a directory";
            throw new IllegalArgumentException(message);
        }

        File[] files = directory.listFiles();
        if (files == null) {  // null if security restricted
            throw new IOException("Failed to list contents of " + directory);
        }

        IOException exception = null;
        for (File file : files) {
            try {
                delete(file);
            } catch (IOException ioe) {
                exception = ioe;
            }
        }

        if (null != exception) {
            throw exception;
        }
    }

    public static void writeStringToFile(File file, String data, String encoding)
            throws IOException {
        OutputStream os = null;
        try {
            os = new FileOutputStream(file);
            os.write(data.getBytes(encoding));
        } finally {
            if (null != os) {
                os.close();
            }
        }
    }

    public static boolean isGzipStream(byte[] bytes) {
        if (bytes == null || bytes.length < 2) {
            return false;
        }

        return GZIPInputStream.GZIP_MAGIC == ((bytes[1] << 8 | bytes[0]) & 0xFFFF);
    }

    /*
     * Reads unsigned byte.
     */
    private static int readUByte(InputStream in) throws IOException {
        int b = in.read();
        if (b == -1) {
            throw new EOFException();
        }
        if (b < -1 || b > 255) {
            // Report on this.in, not argument in; see read{Header, Trailer}.
            throw new IOException(".read() returned value out of range -1..255: " + b);
        }
        return b;
    }

    public static byte[] tryDecompress(byte[] raw) throws Exception {
        if (!isGzipStream(raw)) {
            return raw;
        }

        GZIPInputStream gis
                = new GZIPInputStream(new ByteArrayInputStream(raw));
        ByteArrayOutputStream out
                = new ByteArrayOutputStream();

        com.aliyun.openservices.eas.discovery.utils.IOUtils.copy(gis, out);

        return out.toByteArray();
    }

    public static File makeSureParentDirExists(String path) {
        File file = new File(path);
        if ((!file.exists() || !file.isDirectory()) && !file.mkdirs()) {
            throw new IllegalStateException("failed to create cache dir: " + DiscoveryClient.getCacheDir());
        }

        return file;
    }

    public static File createFileIfNessary(String filePath) throws Exception {
        File file = new File(filePath);
        if (!file.exists()) {
            if (!file.createNewFile() && !file.exists()) // add another !file.exists() to avoid conflicted creating-new-file from multi-instances
            {
                throw new IllegalStateException("failed to create cache file");
            }
        }

        return file;
    }
}