java - 流中的数据不完整

Question

我正在从进程流中读取数据。基本上，我使用 Runtime.exec API 运行进程并获取进程输入流。

Runtime rt = Runtime.getRuntime();
process = rt.exec("C:/cygwin/home/grec.exe");
InputStream is = process.getInputStream();

然后我将流程的输出收集为 --

            BufferedReader in = new BufferedReader(is);         
            char[] ls = new char[s.available()];
            ls.read(ls);
            String output = new String(ls);

但是，当我打印字符串输出时，我得到了 --

  break [loc]     Add a breakpoint at [file:]line or template
  callflow [val]  Enable call flow tracing
  next            Execute the over instruction, stepping over calls
  over            Execute the current instruction hierarchy

但实际输出是——

  break [loc]     Add a breakpoint at [file:]line or template
  callflow [val]  Enable call flow tracing 
  next            Execute the over instruction, stepping over calls
  over            Execute the current instruction hierarchy
  print <xpath>   Print the value of an XPath expression
 profile [val]   Turn profiler on or off
 reload          Reload the script contents
 run             Restart the script
 step            Execute the next instruction, stepping into calls
 verbose         Turn on verbose (-v) output logging
 where           Show the backtrace of template calls
 quit            Quit debugger

也就是说，输出的一部分被截断，但代码不会抛出异常。我尝试增加 BufferedReader 的大小并增加数组 ls 的大小。我无法找到此行为的原因。任何有关可能导致此问题的原因的提示或指示都将受到高度赞赏。

Answer 1

使用循环处理所有信息并读取直到流末尾。

Inputstream.available() 没有达到您的预期:

Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking by the next invocation of a method for this input stream.

http://docs.oracle.com/javase/6/docs/api/java/io/InputStream.html#available%28%29