字符串和字节[]问题java

Question

I am converting a String to byte[] and then again byte[] to String in java using the getbytes() and String constructor,

String message = "Hello World";
byte[] message1 = message.getbytes();

using PipedInput/OutputStream I send this to another thread, where,

byte[] getit = new byte[1000];
pipedinputstream.read(getit);
print(new String(getit));

This last print result in 1000 to be printed... I want the actual string length. How can i do that?

Answer 1

When reading the String, you need to get the number of bytes read, and give the length to your String:

byte[] getit = new byte[1000];
int readed = pipedinputstream.read(getit);
print(new String(getit, 0, readed));

Note that if your String is longer than 1000 bytes, it will be truncated.

Answer 2

You are ignoring the number of bytes read. Do it as below:

  byte[] getit = new byte[1000]; 
  int bytesRead = pipedinputstream.read(getit); 
  print(new String(getit, 0, bytesRead).length()); 

Answer 3

public String getText (byte[] arr)
{
StringBuilder sb = new StringBuilder (arr.length);

for (byte b: arr)
    if (b != 32)
        sb.append ((char) b);

return sb.toString ();
}

not so clean, but should work.

Answer 4

I am converting a String to byte[] and then again byte[] to String

Why? The round trip is guaranteed not to work. String is not a container for binary data. Don't do this. Stop beating your head against the wall: the pain will stop after a while.