package org.jboss.weld.examples.pastecode.session;

import org.jboss.weld.examples.pastecode.model.CodeFragment;

import javax.ejb.Lock;
import javax.ejb.LockType;
import javax.ejb.Singleton;
import javax.enterprise.context.ApplicationScoped;
import javax.enterprise.event.Observes;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

/**
 * Holds a log of code fragments added by all users
 * <p/>
 * Threadsafe.
 *
 * @author Pete Muir
 */
@ApplicationScoped
@Singleton
public class CodeFragmentLogger {

    private final List<CodeFragment> log;

    public CodeFragmentLogger() {
        this.log = new ArrayList<CodeFragment>();
    }

    @Lock(LockType.READ)
    public List<CodeFragment> getLog() {
        return Collections.unmodifiableList(log);
    }

    @Lock(LockType.WRITE)
    public void clearLog() {
        this.log.clear();
    }

    @Lock(LockType.WRITE)
    public void addEntry(@Observes CodeFragment codeFragment) {
        this.log.add(codeFragment);
    }

}