java流中read(byte[] b)和read(byte[] b,int off,int len)有什么区别

Question

InputStream in = new FileInputStream(sourcePath);

byte[] b = new byte[1024];
while (in.read(b,0,1023)!=-1) {
System.out.println(new String(b));
};
和
while (in.read(b)!=-1) {
System.out.println(new String(b));
};
有什么区别？

Answer 1

后者定义了流读取时的缓冲区大小