json文件上传怎么校验

public static void main ( String[] args ) { System.out.println ("随便输入一个JSON格式：(直接回车结束)"); Scanner scanner = new Scanner (System.in); ScriptEngineManager sem = new ScriptEngineManager (); ScriptEngine se = sem.getEngineByName ("js"); while (scanner.hasNextLine ()) { String line = scanner.nextLine ().trim (); if ("".equals (line)) { break; } try { System.out.println (se.eval (line)); } catch (ScriptException e) { System.out.println ("不合法的JSON，重新输入："); continue; } } scanner.close (); }