typicalcompilerscannerbyoolex.java

JAVA在编译原理上的应用。

package lolo.test;

import oolex.Input;
import oolex.Scan;
import oolex.Scan.Action;
import oolex.Scan.Alt;
import oolex.Scan.Set;
import oolex.Scan.Word;

import oolex.scanobjects.Int;
import oolex.scanobjects.Flt;
import oolex.scanobjects.JavaIdentifier;
import oolex.scanobjects.JavaWhitespace;
import oolex.scanobjects.QuotedString;
import oolex.scanobjects.SlashSlashComment;
import oolex.scanobjects.HashComment;
import oolex.scanobjects.JavadocComment;

import java.io.InputStreamReader;
import java.io.FileReader;

/** An example to meassure the scanning time using oolex for typical symbols
 * in compiler construction.
 *
 * @author <a href="http://www.inf.uos.de/bernd" target="_blank">Bernd K&uuml;hl</a>
           (<a href="mailto:[e-mail]">[e-mail]</a>)
 */
public class TypicalCompilerScannerByOOlex {
    public static void main(String args[]) throws Exception {
        Action wordAction = new Action () {
            public void action(Scan sender, char[] buf, int off, int len) {
                PrintTypicalCompilerSymbols.word(new String(buf, off, len));
            }
        };
        Action commentAction = new Action () {
            public void action(Scan sender, char[] buf, int off, int len) {
                PrintTypicalCompilerSymbols.comment(new String(buf, off, len));
            }
        };
        
        Scan scanner = new Alt(new Scan[] {
            new Word("<=").setAction(wordAction),
            new Word(">=").setAction(wordAction),
            new Word("==").setAction(wordAction),
            new Word("&&").setAction(wordAction),
            new Word("||").setAction(wordAction),
            new Int().setAction(new Action() {
                public void action(Scan sender, char[] buf, int off, int len) {
                    PrintTypicalCompilerSymbols.integer(new String(buf, off, len));
                }
            }),
            new Flt().setAction(new Action() {
                public void action(Scan sender, char[] buf, int off, int len) {
                    PrintTypicalCompilerSymbols.floating(new String(buf, off, len));
                }
            }),
            new JavaIdentifier().setAction(new Action() {
                public void action(Scan sender, char[] buf, int off, int len) {
                    PrintTypicalCompilerSymbols.identifier(new String(buf, off, len));
                }
            }),
            new JavaWhitespace().setIgnore(false).setAction(new Action() {
                public void action(Scan sender, char[] buf, int off, int len) {
                    PrintTypicalCompilerSymbols.whitespace(new String(buf, off, len));
                }
            }),
            new QuotedString().setAction(new Action() {
                public void action(Scan sender, char[] buf, int off, int len) {
                    PrintTypicalCompilerSymbols.quotedText(new String(buf, off, len));
                }
            }),
            new QuotedString('\'').setAction(new Action() {
                public void action(Scan sender, char[] buf, int off, int len) {
                    PrintTypicalCompilerSymbols.quotedChar(buf[off]);
                }
            }),
        new Set("+-=/*@/!<>?:;|[]{}().,%&", true).setAction(new Action() {
            public void action(Scan sender, char[] buf, int off, int len) {
                    PrintTypicalCompilerSymbols.character(buf[off]);
            }
        }),
        new SlashSlashComment().setAction(commentAction).setIgnore(false),
        new HashComment().setAction(commentAction).setIgnore(false),
        new JavadocComment().setAction(commentAction).setIgnore(false)
        });

        
        int front = 1024, rear = 1024;
        try {
            front = Integer.parseInt(System.getProperty("TypicalCompilerScannerByOOlex.front"));
        } catch (Exception e) {
            System.err.println(e);
        }
        try {
            rear = Integer.parseInt(System.getProperty("TypicalCompilerScannerByOOlex.rear"));
        } catch (Exception e) {
            System.err.println(e);
        }

System.err.println("go (front "+front+", rear "+rear+")...");
        long old = System.currentTimeMillis();
System.err.println("start time\t"+old+"...");
        Input input = new Input(args.length != 0 ? new FileReader(args[0]) :new InputStreamReader(System.in), front, rear);
        while (input.token(scanner))
            ;
            
        long current = System.currentTimeMillis();
System.err.println("end time\t"+current+"...");
        TimeUtil.printMilliSecons("time: ", current-old, System.err);
    }
}