copy File and close opened resource - Android App

Android examples for App:Resource

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Description

copy File and close opened resource

Demo Code


import java.io.Closeable;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.io.Writer;
import java.net.HttpURLConnection;
import java.net.URLConnection;
import java.nio.channels.FileChannel;

public class Main{
    private static final long FILE_COPY_BUFFER_SIZE = ONE_MB * 30;
    public static void copyFile(File srcFile, File destFile,
            boolean preserveFileDate) throws IOException {
        if (srcFile == null) {
            throw new NullPointerException("Source must not be null");
        }/*from  ww  w  .j av a 2 s .  c o  m*/
        if (destFile == null) {
            throw new NullPointerException("Destination must not be null");
        }
        if (srcFile.exists() == false) {
            throw new FileNotFoundException("Source '" + srcFile
                    + "' does not exist");
        }
        if (srcFile.isDirectory()) {
            throw new IOException("Source '" + srcFile
                    + "' exists but is a directory");
        }
        if (srcFile.getCanonicalPath().equals(destFile.getCanonicalPath())) {
            throw new IOException("Source '" + srcFile
                    + "' and destination '" + destFile + "' are the same");
        }
        File parentFile = destFile.getParentFile();
        if (parentFile != null) {
            if (!parentFile.mkdirs() && !parentFile.isDirectory()) {
                throw new IOException("Destination '" + parentFile
                        + "' directory cannot be created");
            }
        }
        if (destFile.exists() && destFile.canWrite() == false) {
            throw new IOException("Destination '" + destFile
                    + "' exists but is read-only");
        }
        doCopyFile(srcFile, destFile, preserveFileDate);
    }
    private static void doCopyFile(File srcFile, File destFile,
            boolean preserveFileDate) throws IOException {
        if (destFile.exists() && destFile.isDirectory()) {
            throw new IOException("Destination '" + destFile
                    + "' exists but is a directory");
        }

        FileInputStream fis = null;
        FileOutputStream fos = null;
        FileChannel input = null;
        FileChannel output = null;
        try {
            fis = new FileInputStream(srcFile);
            fos = new FileOutputStream(destFile);
            input = fis.getChannel();
            output = fos.getChannel();
            long size = input.size();
            long pos = 0;
            long count = 0;
            while (pos < size) {
                count = size - pos > FILE_COPY_BUFFER_SIZE ? FILE_COPY_BUFFER_SIZE
                        : size - pos;
                pos += output.transferFrom(input, pos, count);
            }
        } finally {

            closeQuietly(output);
            closeQuietly(fos);
            closeQuietly(input);
            closeQuietly(fis);
        }

        if (srcFile.length() != destFile.length()) {
            throw new IOException("Failed to copy full contents from '"
                    + srcFile + "' to '" + destFile + "'");
        }
        if (preserveFileDate) {
            destFile.setLastModified(srcFile.lastModified());
        }
    }
    public static void closeQuietly(Reader input) {
        closeQuietly((Closeable) input);
    }
    public static void closeQuietly(Writer output) {
        closeQuietly((Closeable) output);
    }
    public static void closeQuietly(OutputStream output) {
        closeQuietly((Closeable) output);
    }
    public static void closeQuietly(InputStream input) {
        closeQuietly((Closeable) input);
    }
    public static void closeQuietly(Closeable closeable) {
        try {
            if (closeable != null) {
                closeable.close();
            }
        } catch (IOException ioe) {
            // ignore
        }
    }
    public static void close(URLConnection conn) {
        if (conn instanceof HttpURLConnection) {
            ((HttpURLConnection) conn).disconnect();
        }
    }
}

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