parser.java

CMM编译器词法分析及语法分析代码

package try_sw;
import java.util.regex.*;
import java.io.*;
import java.util.*;
import   java.awt.Dimension;
import  java.awt.Color;
import  javax.swing.JFrame;
import  javax.swing.JPanel;
import  javax.swing.JScrollPane;
import  javax.swing.JTree;
import  javax.swing.BoxLayout;
import  javax.swing.tree.TreePath;
import  javax.swing.tree.DefaultMutableTreeNode;
import  javax.swing.tree.DefaultTreeModel;

class ParserError extends Exception{
	private String msg;
	public ParserError(String msg){
		this.msg=msg;
	}
	public String toString(){
		return "ParserError"+msg;
	}
}

public class Parser {
    
	private Stack<String> mys = new Stack<String>(); //mys中存放分析栈
	
	private boolean cut(String ana,String[] inp){//检查两栈的头是否相等[void,1]---value-void
		//ana--analyse stack inp--inputstack
		Pattern pn1= Pattern.compile("value-");
		Pattern pn2 = Pattern.compile("style-");
		Matcher m1= pn1.matcher(ana);
		Matcher m2= pn2.matcher(ana);
		
		if(m1.lookingAt()){//先查value:pass
			ana = m1.replaceFirst("");
			
				
				if(ana.equals(inp[0]))return true;
				
				
			
		}
		else if(m2.lookingAt()){
			ana=m2.replaceFirst("");
			
				if(ana.equals(inp[1]))return true;
				
			
		}
		else{
			
			return false;
		}
		
		return false;
				
	}
	
	private String encode_val(String str){
		
		return "value-"+str;
		
	}
	
	private String encode_typ(String str){
		return "style-"+str;
	}
	
	private boolean ifnt(String str){//if it is an nt
		Pattern pn1= Pattern.compile("value-");
		Pattern pn2 = Pattern.compile("style-");
		Matcher m1= pn1.matcher(str);
		Matcher m2= pn2.matcher(str);
		if(m1.lookingAt()||m2.lookingAt())return false;
		else return true;
	}
	
	private boolean isfirstSibling(DefaultMutableTreeNode a){
		
		DefaultMutableTreeNode tmp = a.getPreviousSibling();
		if(tmp==null)return true;
		else return false;
		
	}
	
	private DefaultMutableTreeNode getnow(DefaultMutableTreeNode nownode){
		
		Pattern pn = Pattern.compile("value-");
		Pattern pn1 = Pattern.compile("style-");
		

		while(true){

		if(nownode.getParent()==null)return nownode;
		String test=(String)nownode.getUserObject();
		//getUserObject有没错误？
		if(pn.matcher(test).lookingAt()||pn1.matcher(test).lookingAt()||nownode.getChildCount()!=0
				||test.equals("@NULL")){
				if(isfirstSibling(nownode)){
					nownode=(DefaultMutableTreeNode) nownode.getParent();
				}else{
		             nownode=nownode.getPreviousSibling();
				}
				
	             //若是总结符或不是首结点，则要去他前一个兄弟
	             //若是非总结符，则去else return之
		}
		else{
			//if(nownode.getUserObject().toString().equals("c"))System.out.println()
			return nownode;
		}//end else
		}//end while
		
		
		
	}
	
	
		public DefaultMutableTreeNode Parse(LLhash llh,Mystack mysta){//树的建立
		//llh里存放llh的规则，mysta里存放输入栈 mys存放分析站
		//mysta.makei();
		Mystack mystb=new Mystack();
		while(!mysta.empty()){
			String[] tmp = mysta.top();
			mysta.pop();
			mystb.push(tmp[0], Integer.parseInt(tmp[1]));
		}//got a normal mystb
		mys.push("value-#");
		mys.push("Start");
		DefaultMutableTreeNode nownode = new DefaultMutableTreeNode("Start",true);
		
		DefaultMutableTreeNode remember = new DefaultMutableTreeNode("Start",true);
		while(true){
			try{
			if(mys.isEmpty())break;
			
			if(ifnt(mys.peek())){
					
				   String[] top = mystb.top(); 
					
				    String[] change={};
				   if(llh.containsKey(mys.peek(), encode_val(top[0]))){
					change=llh.get(mys.peek(), encode_val(top[0]));//1。查找
				   }else if(llh.containsKey(mys.peek(), encode_typ(top[1]))){
					change=llh.get(mys.peek(), encode_typ(top[1]));
					
				   }
				   //goal:parameter:ok,
				    //       return:ok,
					
					
					//DefaultMutableTreeNode r=new DefaultMutableTreeNode(mys.peek(),true);
					
					mys.pop();
					///////////////test
					remember=nownode;
					///////////////test
				   DefaultMutableTreeNode tmp = new DefaultMutableTreeNode("c",true);
					for(String c:change){//2.栈的转变
						if(!c.equals("EPSILON")){mys.push(c);//空集
						tmp= new DefaultMutableTreeNode(c,true);}
						else{
							tmp= new DefaultMutableTreeNode("@NULL",true);
						}
						nownode.add(tmp);
					}//end for
					nownode = getnow(tmp);//incorrect-->Start
					
					
					
					}else{//end if 
			
						//nownode 的问题在cut之前就决定好了，所以这里不用处理nownode
						if(cut(mys.peek(),mystb.top())){//3.两个部分的消去
							mys.pop();
							mystb.pop();
							//mysta.pop();是错的因为有顺序问题
						}else{
							throw new ParserError(mys.peek());
						}//end else
						
					}//end else
		}catch(ParserError pe){//end try
			System.out.println(pe);
		}
		}//end while
		
		//System.out.println(nownode.getChildCount());
		return (DefaultMutableTreeNode)nownode.getRoot();
	}//end Parser
		//done
	/**
	 * @param args
	 * @throws IOException 
	 */
	public static void main(String[] args) throws IOException {
		// TODO Auto-generated method stub

		String a ="abc";
		for(String c:a.split("@"))
		System.out.println(c);
		//DefaultMutableTreeNode dn = new Parser().Parse(, mysta)
		
	}

}