java 使用 ScriptEngineManager 解析邏輯表達式

將表達式替換成js使用的文本格式。然后帶入eval函數。

public class JieXi
{
  public static void main(String[] args) throws Exception {
         String str = "(a or b) and c";
         str = str.replaceAll("or", "||");
         str = str.replaceAll("and", "&&");
         System.out.println(str);
         ScriptEngineManager manager = new ScriptEngineManager();
         ScriptEngine engine = manager.getEngineByName("js");
         engine.put("a",true);
         engine.put("b",false);
         engine.put("c",true);        
         Object result = engine.eval(str);
         System.out.println("結果類型:" + result.getClass().getName() + ",計算結果:" + result);
  
     }
}