1、String –> InputStream

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