解释器模式案例源码Demo

package com.bpj.js; public class Caculator { public int build(String statement){ Node left = null; Node right = null; Node lastNode = null; String[] statements = statement.split(" "); for(int i= 0;i<statements.length;i++){ if("*".equalsIgnoreCase(statements[i])){ left = lastNode; int val= Integer.parseInt(statements[++i]); right = new ValueNode(val); lastNode = new MulNode(left, right); }else if("/".equalsIgnoreCase(statements[i])){ left = lastNode; int val= Integer.parseInt(statements[++i]); right = new ValueNode(val); lastNode = new DivNode(left, right); }else if("%".equalsIgnoreCase(statements[i])){ left = lastNode; int val= Integer.parseInt(statements[++i]); right = new ValueNode(val); lastNode = new ModNode(left, right); }else{ lastNode = new ValueNode(Integer.parseInt(statements[i])); } } return lastNode.interpret(); } }