java复制文件

/**
     * @param sourceFile
     * @param targetFile
     * @throws IOException
     */
    public static void copyFile(File sourceFile, File targetFile)
            throws IOException {
        BufferedInputStream inBuff = null;
        BufferedOutputStream outBuff = null;
        try {
            inBuff = new BufferedInputStream(new FileInputStream(sourceFile));
            outBuff = new BufferedOutputStream(new FileOutputStream(targetFile));

            byte[] b = new byte[1024 * 1024];
            int len;
            while ((len = inBuff.read(b)) != -1) {
                outBuff.write(b, 0, len);
            }
            outBuff.flush();
        } finally {
            if (inBuff != null)
                inBuff.close();
            if (outBuff != null)
                outBuff.close();
        }
    }