java null指针异常

Question

我得到java.lang.NullPointerException的 while ((len = in.read(buf , 0 , buf.length)) >= 0)在下面的方法:

public void copy(String  src, File dst) throws IOException {

  InputStream in = getClass().getResourceAsStream(src); 
        OutputStream out = new FileOutputStream(dst);

        byte[] buf = new byte[1012];
        int len;
        while ((len = in.read(buf , 0 , buf.length)) >= 0) {
            out.write(buf, 0, len);
            buf = null;
        }
        in.close();
        out.close();
    }

我没有得到它.如果我得到解决方案,我会很感激.谢谢你提前.......

Answer 1

你设定

buf = null; 

在第一次迭代中,在第二次buf.length处抛出NullPointerException.