java - 为什么要避免在 java 中使用 Runtime.exec()？

Question

   Process p = Runtime.getRuntime().exec(command);
   is = p.getInputStream();
   byte[] userbytes = new byte[1024];
   is.read(userbytes);

我想在 linux 操作系统中从 java 执行 shell 命令。但是 pmd 报告说不要使用 java Runtime.exec()。为什么？是什么原因 ？ Runtime.exec() 有其他替代方法吗？

Answer 1

除非你被困在一个古老的 JVM 上，java.lang.ProcessBuilder使得指定进程、设置其环境、生成它以及处理其文件描述符变得更加容易。

This class is used to create operating system processes.

Each ProcessBuilder instance manages a collection of process attributes. The start() method creates a new Process instance with those attributes. The start() method can be invoked repeatedly from the same instance to create new subprocesses with identical or related attributes.

...

Starting a new process which uses the default working directory and environment is easy:

 Process p = new ProcessBuilder("myCommand", "myArg").start();

Here is an example that starts a process with a modified working directory and environment:

 ProcessBuilder pb = new ProcessBuilder("myCommand", "myArg1", "myArg2");
 Map<String, String> env = pb.environment();
 env.put("VAR1", "myValue");
 env.remove("OTHERVAR");
 env.put("VAR2", env.get("VAR1") + "suffix");
 pb.directory(new File("myDir"));
 Process p = pb.start();