com.nflabs.zeppelin.server.ZQLSession Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of zeppelin-server Show documentation

There is a newer version: 0.3.3

package com.nflabs.zeppelin.server;

import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import org.apache.log4j.Logger;

import com.nflabs.zeppelin.result.Result;
import com.nflabs.zeppelin.scheduler.Job;
import com.nflabs.zeppelin.scheduler.JobListener;
import com.nflabs.zeppelin.zengine.Z;
import com.nflabs.zeppelin.zengine.ZException;
import com.nflabs.zeppelin.zengine.ZQL;

public class ZQLSession extends Job{
	transient Logger logger = Logger.getLogger(ZQLSession.class);

	private String zql;
	Result error;

	private List zqlPlans;
	
	public ZQLSession(String jobName, JobListener listener) {
		super(jobName, listener);
	}
	
	public void setZQL(String zql){
		this.zql = zql;
		// later we can improve this part. to make it modify current plan.
		zqlPlans = null;
		setStatus(Status.READY);
	}
	
	public List getPlan(){
		reconstructNextReference();
		return zqlPlans;
	}
	
	public String getZQL(){
		return zql;
	}

	private void reconstructNextReference(){
		if(zqlPlans==null) return;
		// reconstruct plan link. in case of restored by gson
		for(Z z : zqlPlans){
			Z next = null;
			for(Z c=z; c!=null; c=c.prev()){
				c.setNext(next);
				next = c;
			}
		}
	}
	
	@Override
	public int progress() {
		return 0;
	}

	@Override
	public Map info() {
		return new HashMap();
	}

	@Override
	protected Object jobRun() throws Throwable {
		LinkedList results = new LinkedList();
		if(zqlPlans==null){
			ZQL zqlEvaluator = new ZQL(zql);
			zqlPlans = zqlEvaluator.compile();
		} else {
			reconstructNextReference();
		}
		
		for(Z zz : zqlPlans){
			try {
				if(zz.isExecuted()==false){
					zz.execute();
				}
				results.add(zz.result());
				zz.release();
			} catch (ZException e) {
				error = new Result(e);
				throw e;
			} 
		}

		return results;
	}

	@Override
	protected boolean jobAbort() {
		// TODO implement
		return false;
		
	}
	
}