Java Parsing Logical Expressions_DangerousRoy’s Blog

java parses logical expressions (strings that perform logical operators) import javax.script.ScriptEngine; import javax.script.ScriptEngineManager; public class expression { public static void main(String[] args) throws Exception { String str = “(a and b) or (c and d)”; 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”,false); engine.put(“d”,true); Object result = engine.eval(str); System.out.println(“Result type: ” + result.getClass().getName() + “, calculation result: ” + result); } } Original address: http://blog.sina.com.cn/s/blog_acdc06250101p5dh.html