dpastprinter.java

SkipOOMiniJOOL教学语言的编译器前端

package edu.ustc.cs.minijool.parser.ast;

import java.util.Iterator;

/**
 * @author manu_s
 *
 */
public class DPASTPrinter extends DPVisitor {

    private static int indent = 0;

    /* (non-Javadoc)
     * @see edu.berkeley.cs164.parser.ast.DCVisitor#visit(edu.berkeley.cs164.parser.ast.Spec)
     */
    public boolean visit(Spec s) {
        printNode(s);
        System.out.println();
        indent += 4;
        for (Iterator iter = s.getProductions().iterator(); iter.hasNext();) {
            Production prod = (Production) iter.next();
            prod.accept(this);
        }
        indent -= 4;
        return false;
    }

    /* (non-Javadoc)
     * @see edu.berkeley.cs164.parser.ast.DCVisitor#visit(edu.berkeley.cs164.parser.ast.Production)
     */
    public boolean visit(Production p) {
        printNode(p);
        System.out.println();
        indent += 4;
        p.getProdName().accept(this);
        for (Iterator iter = p.getRightHandSides().iterator();
            iter.hasNext();
            ) {
            RightHandSide r = (RightHandSide) iter.next();
            r.accept(this);
        }
        indent -= 4;
        return false;
    }

    /* (non-Javadoc)
     * @see edu.berkeley.cs164.parser.ast.DCVisitor#visit(edu.berkeley.cs164.parser.ast.RightHandSide)
     */
    public boolean visit(RightHandSide r) {
        printNode(r);
        System.out.println();
        indent += 4;
        for (Iterator iter = r.getTermsAndNonTerms().iterator();
            iter.hasNext();
            ) {
            NameWithAction n = (NameWithAction) iter.next();
            n.accept(this);
        }
        indent -= 4;
        return false;
    }
    /* (non-Javadoc)
     * @see edu.berkeley.cs164.parser.ast.DCVisitor#visit(edu.berkeley.cs164.parser.ast.SimpleName)
     */
    public boolean visit(SimpleName s) {
        printNode(s);
        System.out.println(" " + s.getIdentifier());
        return false;
    }

    /* (non-Javadoc)
     * @see edu.berkeley.cs164.parser.ast.DCVisitor#visit(edu.berkeley.cs164.parser.ast.Action)
     */
    public boolean visit(Action a) {
        printNode(a);
        System.out.println(
            " " + ((a == Action.NONE) ? "NONE" : a.getActionCode()));
        return false;
    }

    /* (non-Javadoc)
     * @see edu.berkeley.cs164.parser.ast.DCVisitor#visit(edu.berkeley.cs164.parser.ast.NonTerminalRef)
     */
    public boolean visit(NonTerminal n) {
        printNode(n);
        System.out.println();
        indent += 4;
        n.getName().accept(this);
        n.getAction().accept(this);
        indent -= 4;
        return false;
    }

    /* (non-Javadoc)
     * @see edu.berkeley.cs164.parser.ast.DCVisitor#visit(edu.berkeley.cs164.parser.ast.TerminalRef)
     */
    public boolean visit(Terminal t) {
        printNode(t);
        System.out.println();
        indent += 4;
        t.getName().accept(this);
        t.getAction().accept(this);
        indent -= 4;
        return false;
    }

    /* (non-Javadoc)
     * @see edu.berkeley.cs164.parser.ast.DCVisitor#visit(edu.berkeley.cs164.parser.ast.Epsilon)
     */
    public boolean visit(Epsilon e) {
        printNode(e);
        System.out.println();
        indent += 4;
        e.getAction().accept(this);
        indent -= 4;
        return false;
    }

    private static void printNode(DPASTNode node) {
        for (int i = 0; i < indent; i++) {
            System.out.print(' ');
        }
        System.out.print(getShortName(node.getClass()));
    }

    private static String getShortName(Class c) {
        String fullName = c.getName();
        int pos = fullName.lastIndexOf('.');
        if (pos == -1)
            return fullName;
        return fullName.substring(pos + 1);
    }

}