CopyFileFromCommonsIo.java

package bs.util.tool.commongui.utils;

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;

/**
 * 复制文件，方法直接拷贝自commons-io-1.4的org.apache.commons.io.FileUtils.copyFile(srcFile, destFile).
 */
public class CopyFileFromCommonsIo {

    public static void copyFile(File srcFile, File destFile) throws IOException {
        copyFile(srcFile, destFile, true);
    }

    public static void copyFile(File srcFile, File destFile, boolean preserveFileDate) throws IOException {
        if (srcFile == null) {
            throw new NullPointerException("Source must not be null");
        }
        if (destFile == null) {
            throw new NullPointerException("Destination must not be null");
        }
        if (!srcFile.exists()) {
            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");
        }
        if ((destFile.getParentFile() != null) && (!destFile.getParentFile().exists())
                && (!destFile.getParentFile().mkdirs())) {
            throw new IOException("Destination '" + destFile + "' directory cannot be created");
        }

        if ((destFile.exists()) && (!destFile.canWrite())) {
            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 input = new FileInputStream(srcFile);
        try {
            FileOutputStream output = new FileOutputStream(destFile);
            try {
                copy(input, output);
            } finally {
                closeQuietly(output);
            }
        } finally {
            closeQuietly(input);
        }

        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 int copy(InputStream input, OutputStream output) throws IOException {
        long count = copyLarge(input, output);
        if (count > 2147483647L) {
            return -1;
        }
        return (int) count;
    }

    public static long copyLarge(InputStream input, OutputStream output) throws IOException {
        byte[] buffer = new byte[4096];
        long count = 0L;
        int n = 0;
        while (-1 != (n = input.read(buffer))) {
            output.write(buffer, 0, n);
            count += n;
        }
        return count;
    }

    public static void closeQuietly(InputStream input) {
        try {
            if (input != null)
                input.close();
        } catch (IOException ioe) {
        }
    }

    public static void closeQuietly(OutputStream output) {
        try {
            if (output != null)
                output.close();
        } catch (IOException ioe) {
        }
    }

}