java 中InputStream,String,File之间的相互转化对比

InputStream String2InputStream(String str){ ByteArrayInputStream stream = new ByteArrayInputStream(str.getBytes()); return stream;}

String inputStream2String(InputStream is){ BufferedReader in = new BufferedReader(new InputStreamReader(is)); StringBuffer buffer = new StringBuffer(); String line = ""; while ((line = in.readLine()) != null){  buffer.append(line); } return buffer.toString();}

String all_content=null;  try {  all_content =new String();   InputStream ins = 获取的输入流;   ByteArrayOutputStream outputstream = new ByteArrayOutputStream();  byte[] str_b = new byte[1024];  int i = -1;  while ((i=ins.read(str_b)) > 0) {   outputstream.write(str_b,0,i);  }  all_content = outputstream.toString(); } catch (Exception e) {e.printStackTrace();  }

InputStream in = new InputStream(new FileInputStream(File));

public void inputstreamtofile(InputStream ins,File file){OutputStream os = new FileOutputStream(file);int bytesRead = 0;byte[] buffer = new byte[8192];while ((bytesRead = ins.read(buffer, 0, 8192)) != -1) {os.write(buffer, 0, bytesRead);}os.close();ins.close();}