String、InputStream、OutputStream格式转换

1、String –> InputStream

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

或者

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

2、InputStream–>String

InputStreaminput;

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、String –> OutputStream

OutputStream os = System.out;
os.write(string.getBytes())

4、OutputStream –> String

ByteArrayOutputStream baos = new ByteArrayOutputStream();
//向OutPutStream中写入，如 message.writeTo(baos);
String str = baos.toString();