15、关于String,File,InputStream之间的相互转换

1、介绍了关于String,File,InputStream之间的相互转换

      1.1  String2InputStream

        /** * String2InputStream(String str)的工具方法 *  * @param str *            需要转换的字符串str * @return 返回的是字符串str转换为inputstream的结果 */public static InputStream String2InputStream(String str) {ByteArrayInputStream stream = new ByteArrayInputStream(str.getBytes());return stream;}

     1.2  inputStream2String(InputStream is)  ;  String inputStream2String(InputStream is, String charset)

        /** * inputStream2String(InputStream is) *  * @param is *            输入流InputStream is * @return 输入流InputStream is转换为的String */public static String inputStream2String(InputStream is) {StringBuffer buffer = null;BufferedReader in = null;try {in = new BufferedReader(new InputStreamReader(is));buffer = new StringBuffer();String line = "";while ((line = in.readLine()) != null) {buffer.append(line);}} catch (Exception e) {throw new RuntimeException("在调用Utils.inputStream2String(InputStream is)发生异常！！！");}return buffer.toString();}/** * inputStream2String(InputStream is, String charset) *  * @param is *            输入流InputStream is * @param charset *            字符集String charset * @return 输入流InputStream is,字符集String charset转换为的String */public static String inputStream2String(InputStream is, String charset) {ByteArrayOutputStream baos = null;try {baos = new ByteArrayOutputStream();byte data[] = new byte[1024];int len = -1;while ((len = is.read(data)) != -1) {baos.write(data, 0, len);}String a = baos.toString(charset);return baos.toString(charset);} catch (IOException e) {throw new RuntimeException("在调用Utils.inputStream2String(InputStream is,String charset)发生异常！！！");} finally {if (null != baos) {try {baos.close();} catch (IOException e) {throw new RuntimeException("在调用Utils.inputStream2String(InputStream is, String charset)发生异常！！！");}baos = null;}}}

         1.3  file2InputStream

/** * file2InputStream(File file) *  * @param file *            文件 File file * @return 文件File转换为的InputStream */public static InputStream file2InputStream(File file) {InputStream in = null;try {in = new FileInputStream(file);return in;} catch (FileNotFoundException e) {throw new RuntimeException("在调用Utils.file2InputStream(File file)发生异常！！！");}}/** * file2InputStream(String filenPath) *  * @param filenPath *            文件 File的具体路径 * @return 文件File转换为的InputStream */public static InputStream file2InputStream(String filenPath) {InputStream in = null;File file = null;try {file = new File(filenPath);in = new FileInputStream(file);return in;} catch (FileNotFoundException e) {throw new RuntimeException("在调用Utils.file2InputStream(String filenPath)发生异常！！！");}}

       1.4  inputstreamtofile

        /** * inputstreamtofile(InputStream ins, File file) *  * @param ins *            输入流InputStream ins * @param file *            输入流InputStream ins转换的文件 */public static void inputstreamtofile(InputStream ins, File file) {OutputStream os = null;try {os = new FileOutputStream(file);int bytesRead = 0;byte[] buffer = new byte[1024];while ((bytesRead = ins.read(buffer)) != -1) {os.write(buffer, 0, bytesRead);}} catch (Exception e) {throw new RuntimeException("在调用Utils.inputstreamtofile(InputStream ins, File file)发生异常！！！");} finally {try {if (os != null)os.close();if (ins != null) {ins.close();}} catch (IOException e) {throw new RuntimeException("在调用Utils.inputstreamtofile(InputStream ins, File file)发生异常！！！");}}}public static void inputstreamtofile(InputStream ins, String filePath) {OutputStream os = null;File file = null;try {file = new File(filePath);os = new FileOutputStream(file);int bytesRead = 0;byte[] buffer = new byte[1024];while ((bytesRead = ins.read(buffer)) != -1) {os.write(buffer, 0, bytesRead);}} catch (Exception e) {throw new RuntimeException("在调用Utils.inputstreamtofile(InputStream ins, File file)发生异常！！！");} finally {try {if (os != null)os.close();if (ins != null) {ins.close();}} catch (IOException e) {throw new RuntimeException("在调用Utils.inputstreamtofile(InputStream ins, File file)发生异常！！！");}}}