java之String, inputStream与Reader转换

参考链接： Java Reader类

1、String –> InputStream 

 InputStrem is = new ByteArrayInputStream(str.getBytes());

或者

ByteArrayInputStream stream= new ByteArrayInputStream(str.getBytes()); 

  2、InputStream–>String 

 inputStream input;

StringBuffer out = new StringBuffer();

     byte[] b = new byte[4096];

     for (int n; (n = input.read(b)) != -1;) {

          out.append(new String(b, 0, n));

     }

out.toString(); 

 3、Reader –>String 

 BufferedReader in = new BufferedReader(new InputStreamReader(is));

StringBuffer buffer = new StringBuffer();

String line = " ";

while ((line = in.readLine()) != null){

     buffer.append(line);

}

return buffer.toString(); 

 4、String–>Reader 

 Reader reader = null;

BufferedReader r = new BufferedReader(reader);

StringBuilder b = new StringBuilder();

String line;

while((line=r.readLine())!=null) {

     b.append(line);

     b.append(“\r\n”);

}

b.toString();