Search code examples
javastringbytearrayoutputstream

Why String receiver's size is smaller than original ByteArrayOutputStream's size when I call toString()

I'm in front of a curious problem. Some code is better than long story:

ByteArrayOutputStream buffer = new ByteArrayOutputStream();
buffer.write(...); // I write byte[] data
// In debugger I can see that buffer's count = 449597
String szData = buffer.toString();
int iSizeData = buffer.size();
// But here, szData's count = 240368
// & iSizeData = 449597

So my question is: why szData doesn't contain all the buffer's data? (only one Thread run this code) because after that kind of operation, I don't want szData.charAt(iSizeData - 1) crashes!

EDIT: szData.getBytes().length = 450566. There is encoding problems I think. Better use a byte[] instead of a String finally?

Solution

  • In Java, char ≠ byte, depending on the default character coding of the platform, char can occupy up to 4 bytes in memory. You work either with bytes (binary data), or with characters (strings), you cannot (easily) switch between them.

    For String operations like strncasecmp in C, use the methods of the String class, e.g. String.compareToIgnoreCase(String str). Also have a look at the StringUtils class from the Apache Commons Lang library.