• Android-FileIOUtils工具类


    文件读写相关工具类

    public final class FileIOUtils {
    
        private FileIOUtils() {
            throw new UnsupportedOperationException("u can't instantiate me...");
        }
    
        private static final String LINE_SEP = System.getProperty("line.separator");
    
        private static int sBufferSize = 8192;
    
        /**
         * 将输入流写入文件
         *
         * @param filePath 路径
         * @param is       输入流
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromIS(final String filePath, final InputStream is) {
            return writeFileFromIS(getFileByPath(filePath), is, false);
        }
    
        /**
         * 将输入流写入文件
         *
         * @param filePath 路径
         * @param is       输入流
         * @param append   是否追加在文件末
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromIS(final String filePath, final InputStream is, final boolean append) {
            return writeFileFromIS(getFileByPath(filePath), is, append);
        }
    
        /**
         * 将输入流写入文件
         *
         * @param file 文件
         * @param is   输入流
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromIS(final File file, final InputStream is) {
            return writeFileFromIS(file, is, false);
        }
    
        /**
         * 将输入流写入文件
         *
         * @param file   文件
         * @param is     输入流
         * @param append 是否追加在文件末
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromIS(final File file, final InputStream is, final boolean append) {
            if (!createOrExistsFile(file) || is == null) return false;
            OutputStream os = null;
            try {
                os = new BufferedOutputStream(new FileOutputStream(file, append));
                byte data[] = new byte[sBufferSize];
                int len;
                while ((len = is.read(data, 0, sBufferSize)) != -1) {
                    os.write(data, 0, len);
                }
                return true;
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            } finally {
                CloseUtils.closeIO(is, os);
            }
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param filePath 文件路径
         * @param bytes    字节数组
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByStream(final String filePath, final byte[] bytes) {
            return writeFileFromBytesByStream(getFileByPath(filePath), bytes, false);
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param filePath 文件路径
         * @param bytes    字节数组
         * @param append   是否追加在文件末
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByStream(final String filePath, final byte[] bytes, final boolean append) {
            return writeFileFromBytesByStream(getFileByPath(filePath), bytes, append);
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param file  文件
         * @param bytes 字节数组
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByStream(final File file, final byte[] bytes) {
            return writeFileFromBytesByStream(file, bytes, false);
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param file   文件
         * @param bytes  字节数组
         * @param append 是否追加在文件末
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByStream(final File file, final byte[] bytes, final boolean append) {
            if (bytes == null || !createOrExistsFile(file)) return false;
            BufferedOutputStream bos = null;
            try {
                bos = new BufferedOutputStream(new FileOutputStream(file, append));
                bos.write(bytes);
                return true;
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            } finally {
                CloseUtils.closeIO(bos);
            }
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param filePath 文件路径
         * @param bytes    字节数组
         * @param isForce  是否写入文件
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByChannel(final String filePath, final byte[] bytes, final boolean isForce) {
            return writeFileFromBytesByChannel(getFileByPath(filePath), bytes, false, isForce);
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param filePath 文件路径
         * @param bytes    字节数组
         * @param append   是否追加在文件末
         * @param isForce  是否写入文件
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByChannel(final String filePath, final byte[] bytes, final boolean append, final boolean isForce) {
            return writeFileFromBytesByChannel(getFileByPath(filePath), bytes, append, isForce);
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param file    文件
         * @param bytes   字节数组
         * @param isForce 是否写入文件
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByChannel(final File file, final byte[] bytes, final boolean isForce) {
            return writeFileFromBytesByChannel(file, bytes, false, isForce);
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param file    文件
         * @param bytes   字节数组
         * @param append  是否追加在文件末
         * @param isForce 是否写入文件
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByChannel(final File file, final byte[] bytes, final boolean append, final boolean isForce) {
            if (bytes == null) return false;
            FileChannel fc = null;
            try {
                fc = new FileOutputStream(file, append).getChannel();
                fc.position(fc.size());
                fc.write(ByteBuffer.wrap(bytes));
                if (isForce) fc.force(true);
                return true;
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            } finally {
                CloseUtils.closeIO(fc);
            }
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param filePath 文件路径
         * @param bytes    字节数组
         * @param isForce  是否写入文件
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByMap(final String filePath, final byte[] bytes, final boolean isForce) {
            return writeFileFromBytesByMap(filePath, bytes, false, isForce);
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param filePath 文件路径
         * @param bytes    字节数组
         * @param append   是否追加在文件末
         * @param isForce  是否写入文件
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByMap(final String filePath, final byte[] bytes, final boolean append, final boolean isForce) {
            return writeFileFromBytesByMap(getFileByPath(filePath), bytes, append, isForce);
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param file    文件
         * @param bytes   字节数组
         * @param isForce 是否写入文件
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByMap(final File file, final byte[] bytes, final boolean isForce) {
            return writeFileFromBytesByMap(file, bytes, false, isForce);
        }
    
        /**
         * 将字节数组写入文件
         *
         * @param file    文件
         * @param bytes   字节数组
         * @param append  是否追加在文件末
         * @param isForce 是否写入文件
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromBytesByMap(final File file, final byte[] bytes, final boolean append, final boolean isForce) {
            if (bytes == null || !createOrExistsFile(file)) return false;
            FileChannel fc = null;
            try {
                fc = new FileOutputStream(file, append).getChannel();
                MappedByteBuffer mbb = fc.map(FileChannel.MapMode.READ_WRITE, fc.size(), bytes.length);
                mbb.put(bytes);
                if (isForce) mbb.force();
                return true;
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            } finally {
                CloseUtils.closeIO(fc);
            }
        }
    
        /**
         * 将字符串写入文件
         *
         * @param filePath 文件路径
         * @param content  写入内容
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromString(final String filePath, final String content) {
            return writeFileFromString(getFileByPath(filePath), content, false);
        }
    
        /**
         * 将字符串写入文件
         *
         * @param filePath 文件路径
         * @param content  写入内容
         * @param append   是否追加在文件末
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromString(final String filePath, final String content, final boolean append) {
            return writeFileFromString(getFileByPath(filePath), content, append);
        }
    
        /**
         * 将字符串写入文件
         *
         * @param file    文件
         * @param content 写入内容
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromString(final File file, final String content) {
            return writeFileFromString(file, content, false);
        }
    
        /**
         * 将字符串写入文件
         *
         * @param file    文件
         * @param content 写入内容
         * @param append  是否追加在文件末
         * @return {@code true}: 写入成功<br>{@code false}: 写入失败
         */
        public static boolean writeFileFromString(final File file, final String content, final boolean append) {
            if (file == null || content == null) return false;
            if (!createOrExistsFile(file)) return false;
            BufferedWriter bw = null;
            try {
                bw = new BufferedWriter(new FileWriter(file, append));
                bw.write(content);
                return true;
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            } finally {
                CloseUtils.closeIO(bw);
            }
        }
    
        ///////////////////////////////////////////////////////////////////////////
        // the divide line of write and read
        ///////////////////////////////////////////////////////////////////////////
    
        /**
         * 读取文件到字符串链表中
         *
         * @param filePath 文件路径
         * @return 字符串链表中
         */
        public static List<String> readFile2List(final String filePath) {
            return readFile2List(getFileByPath(filePath), null);
        }
    
        /**
         * 读取文件到字符串链表中
         *
         * @param filePath    文件路径
         * @param charsetName 编码格式
         * @return 字符串链表中
         */
        public static List<String> readFile2List(final String filePath, final String charsetName) {
            return readFile2List(getFileByPath(filePath), charsetName);
        }
    
        /**
         * 读取文件到字符串链表中
         *
         * @param file 文件
         * @return 字符串链表中
         */
        public static List<String> readFile2List(final File file) {
            return readFile2List(file, 0, 0x7FFFFFFF, null);
        }
    
        /**
         * 读取文件到字符串链表中
         *
         * @param file        文件
         * @param charsetName 编码格式
         * @return 字符串链表中
         */
        public static List<String> readFile2List(final File file, final String charsetName) {
            return readFile2List(file, 0, 0x7FFFFFFF, charsetName);
        }
    
        /**
         * 读取文件到字符串链表中
         *
         * @param filePath 文件路径
         * @param st       需要读取的开始行数
         * @param end      需要读取的结束行数
         * @return 字符串链表中
         */
        public static List<String> readFile2List(final String filePath, final int st, final int end) {
            return readFile2List(getFileByPath(filePath), st, end, null);
        }
    
        /**
         * 读取文件到字符串链表中
         *
         * @param filePath    文件路径
         * @param st          需要读取的开始行数
         * @param end         需要读取的结束行数
         * @param charsetName 编码格式
         * @return 字符串链表中
         */
        public static List<String> readFile2List(final String filePath, final int st, final int end, final String charsetName) {
            return readFile2List(getFileByPath(filePath), st, end, charsetName);
        }
    
        /**
         * 读取文件到字符串链表中
         *
         * @param file 文件
         * @param st   需要读取的开始行数
         * @param end  需要读取的结束行数
         * @return 字符串链表中
         */
        public static List<String> readFile2List(final File file, final int st, final int end) {
            return readFile2List(file, st, end, null);
        }
    
        /**
         * 读取文件到字符串链表中
         *
         * @param file        文件
         * @param st          需要读取的开始行数
         * @param end         需要读取的结束行数
         * @param charsetName 编码格式
         * @return 字符串链表中
         */
        public static List<String> readFile2List(final File file, final int st, final int end, final String charsetName) {
            if (!isFileExists(file)) return null;
            if (st > end) return null;
            BufferedReader reader = null;
            try {
                String line;
                int curLine = 1;
                List<String> list = new ArrayList<>();
                if (isSpace(charsetName)) {
                    reader = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
                } else {
                    reader = new BufferedReader(new InputStreamReader(new FileInputStream(file), charsetName));
                }
                while ((line = reader.readLine()) != null) {
                    if (curLine > end) break;
                    if (st <= curLine && curLine <= end) list.add(line);
                    ++curLine;
                }
                return list;
            } catch (IOException e) {
                e.printStackTrace();
                return null;
            } finally {
                CloseUtils.closeIO(reader);
            }
        }
    
        /**
         * 读取文件到字符串中
         *
         * @param filePath 文件路径
         * @return 字符串
         */
        public static String readFile2String(final String filePath) {
            return readFile2String(getFileByPath(filePath), null);
        }
    
        /**
         * 读取文件到字符串中
         *
         * @param filePath    文件路径
         * @param charsetName 编码格式
         * @return 字符串
         */
        public static String readFile2String(final String filePath, final String charsetName) {
            return readFile2String(getFileByPath(filePath), charsetName);
        }
    
        /**
         * 读取文件到字符串中
         *
         * @param file 文件
         * @return 字符串
         */
        public static String readFile2String(final File file) {
            return readFile2String(file, null);
        }
    
        /**
         * 读取文件到字符串中
         *
         * @param file        文件
         * @param charsetName 编码格式
         * @return 字符串
         */
        public static String readFile2String(final File file, final String charsetName) {
            if (!isFileExists(file)) return null;
            BufferedReader reader = null;
            try {
                StringBuilder sb = new StringBuilder();
                if (isSpace(charsetName)) {
                    reader = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
                } else {
                    reader = new BufferedReader(new InputStreamReader(new FileInputStream(file), charsetName));
                }
                String line;
                while ((line = reader.readLine()) != null) {
                    sb.append(line).append(LINE_SEP);
                }
                // delete the last line separator
                return sb.delete(sb.length() - LINE_SEP.length(), sb.length()).toString();
            } catch (IOException e) {
                e.printStackTrace();
                return null;
            } finally {
                CloseUtils.closeIO(reader);
            }
        }
    
        /**
         * 读取文件到字节数组中
         *
         * @param filePath 文件路径
         * @return 字符数组
         */
        public static byte[] readFile2BytesByStream(final String filePath) {
            return readFile2BytesByStream(getFileByPath(filePath));
        }
    
        /**
         * 读取文件到字节数组中
         *
         * @param file 文件
         * @return 字符数组
         */
        public static byte[] readFile2BytesByStream(final File file) {
            if (!isFileExists(file)) return null;
            FileInputStream fis = null;
            ByteArrayOutputStream os = null;
            try {
                fis = new FileInputStream(file);
                os = new ByteArrayOutputStream();
                byte[] b = new byte[sBufferSize];
                int len;
                while ((len = fis.read(b, 0, sBufferSize)) != -1) {
                    os.write(b, 0, len);
                }
                return os.toByteArray();
            } catch (IOException e) {
                e.printStackTrace();
                return null;
            } finally {
                CloseUtils.closeIO(fis, os);
            }
        }
    
        /**
         * 读取文件到字节数组中
         *
         * @param filePath 文件路径
         * @return 字符数组
         */
        public static byte[] readFile2BytesByChannel(final String filePath) {
            return readFile2BytesByChannel(getFileByPath(filePath));
        }
    
        /**
         * 读取文件到字节数组中
         *
         * @param file 文件
         * @return 字符数组
         */
        public static byte[] readFile2BytesByChannel(final File file) {
            if (!isFileExists(file)) return null;
            FileChannel fc = null;
            try {
                fc = new RandomAccessFile(file, "r").getChannel();
                ByteBuffer byteBuffer = ByteBuffer.allocate((int) fc.size());
                while (true) {
                    if (!((fc.read(byteBuffer)) > 0)) break;
                }
                return byteBuffer.array();
            } catch (IOException e) {
                e.printStackTrace();
                return null;
            } finally {
                CloseUtils.closeIO(fc);
            }
        }
    
        /**
         * 读取文件到字节数组中
         *
         * @param filePath 文件路径
         * @return 字符数组
         */
        public static byte[] readFile2BytesByMap(final String filePath) {
            return readFile2BytesByMap(getFileByPath(filePath));
        }
    
        /**
         * 读取文件到字节数组中
         *
         * @param file 文件
         * @return 字符数组
         */
        public static byte[] readFile2BytesByMap(final File file) {
            if (!isFileExists(file)) return null;
            FileChannel fc = null;
            try {
                fc = new RandomAccessFile(file, "r").getChannel();
                int size = (int) fc.size();
                MappedByteBuffer mbb = fc.map(FileChannel.MapMode.READ_ONLY, 0, size).load();
                byte[] result = new byte[size];
                mbb.get(result, 0, size);
                return result;
            } catch (IOException e) {
                e.printStackTrace();
                return null;
            } finally {
                CloseUtils.closeIO(fc);
            }
        }
    
        /**
         * 设置缓冲区尺寸
         *
         * @param bufferSize 缓冲区大小
         */
        public static void setBufferSize(final int bufferSize) {
            sBufferSize = bufferSize;
        }
    
        private static File getFileByPath(final String filePath) {
            return isSpace(filePath) ? null : new File(filePath);
        }
    
        private static boolean createOrExistsFile(final String filePath) {
            return createOrExistsFile(getFileByPath(filePath));
        }
    
        private static boolean createOrExistsFile(final File file) {
            if (file == null) return false;
            if (file.exists()) return file.isFile();
            if (!createOrExistsDir(file.getParentFile())) return false;
            try {
                return file.createNewFile();
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            }
        }
    
        private static boolean createOrExistsDir(final File file) {
            return file != null && (file.exists() ? file.isDirectory() : file.mkdirs());
        }
    
        private static boolean isFileExists(final File file) {
            return file != null && file.exists();
        }
    
        private static boolean isSpace(final String s) {
            if (s == null) return true;
            for (int i = 0, len = s.length(); i < len; ++i) {
                if (!Character.isWhitespace(s.charAt(i))) {
                    return false;
                }
            }
            return true;
        }
    }
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  • 原文地址:https://www.cnblogs.com/android-deli/p/10322151.html
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