view flys-artifacts/src/main/java/de/intevation/flys/artifacts/FlowVelocityMeasurementArtifact.java @ 5779:ebec12def170

Datacage: Add a pool of builders to make it multi threadable. XML DOM is not thread safe. Therefore the old implementation only allowed one thread to use the builder at a time. As the complexity of the configuration has increased over time this has become a bottleneck of the whole application because it took quiet some time to build a result. Furthermore the builder code path is visited very frequent. So many concurrent requests were piled up resulting in long waits for the users. To mitigate this problem a round robin pool of builders is used now. Each of the pooled builders has an independent copy of the XML template and can be run in parallel. The number of builders is determined by the system property 'flys.datacage.pool.size'. It defaults to 4.
author Sascha L. Teichmann <teichmann@intevation.de>
date Sun, 21 Apr 2013 12:48:09 +0200
parents a2735a4bf75e
children
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package de.intevation.flys.artifacts;

import java.util.ArrayList;
import java.util.List;

import org.apache.log4j.Logger;
import org.w3c.dom.Document;

import de.intevation.artifactdatabase.state.DefaultOutput;
import de.intevation.artifactdatabase.state.Facet;
import de.intevation.artifactdatabase.state.FacetActivity;
import de.intevation.artifactdatabase.state.State;
import de.intevation.artifacts.Artifact;
import de.intevation.artifacts.ArtifactFactory;
import de.intevation.artifacts.CallMeta;
import de.intevation.artifacts.common.utils.XMLUtils;
import de.intevation.flys.model.FlowVelocityMeasurementValue;
import de.intevation.flys.artifacts.model.minfo.FlowVelocityMeasurementFacet;
import de.intevation.flys.artifacts.model.minfo.FlowVelocityMeasurementFactory;
import de.intevation.flys.artifacts.states.StaticState;

import de.intevation.flys.artifacts.model.FacetTypes;


/** Artefact to access flow velocity measurements. */
public class FlowVelocityMeasurementArtifact
extends      StaticFLYSArtifact
implements   FacetTypes
{
    /** The logger for this class. */
    private static Logger logger =
        Logger.getLogger(FlowVelocityMeasurementArtifact.class);

    /** Artifact key name. */
    private static final String NAME = "flowvelocitymeasurement";

    /** Spawn only inactive facets. */
    static {
        // TODO: Move to configuration.
        FacetActivity.Registry.getInstance()
            .register(NAME, FacetActivity.INACTIVE);
    }

    /** Need to give the state an id. */
    public static final String STATIC_STATE_NAME =
        "state.flowvelocitymeasurement.static";

    /** One and only state to be in. */
    protected transient State state = null;

    protected String DATA_NAME = "ID";

    /**
     * Trivial Constructor.
     */
    public FlowVelocityMeasurementArtifact() {
        logger.debug("FlowVelocityMeasurementArtifact.FlowVelocityMeasurementArtifact");
    }


    /** Get artifact key name. */
    @Override
    public String getName() {
        return NAME;
    }


    /** Create a new state with bogus output. */
    protected State spawnState() {
        state = new StaticState(STATIC_STATE_NAME);
        List<Facet> fs = getFacets(STATIC_STATE_NAME);
        DefaultOutput output = new DefaultOutput(
            "general",
            "general",
            "image/png",
            fs,
            "chart");

        state.getOutputs().add(output);

        return state;
    }


    /**
     * Gets called from factory, to set things up.
     */
    @Override
    public void setup(
        String          identifier,
        ArtifactFactory factory,
        Object          context,
        CallMeta        callMeta,
        Document        data)
    {
        logger.debug("FlowVelocityMeasurementArtifact.setup");

        state = new StaticState(STATIC_STATE_NAME);

        if (logger.isDebugEnabled()) {
            logger.debug(XMLUtils.toString(data));
        }

        List<Facet> fs = new ArrayList<Facet>();
        String code = getDatacageIDValue(data);

        if (code != null) {
            // parse code, interact with factory, add real facets.
            // store relevant parts of code as data.
            Facet facet = new FlowVelocityMeasurementFacet(
                FLOW_VELOCITY_MEASUREMENT,
                "flowvelocity-name");
            fs.add(facet);
            addFacets(state.getID(), fs);
            addStringData(DATA_NAME, code);
        }

        spawnState();
        super.setup(identifier, factory, context, callMeta, data);
    }


    /**
     * Get a list containing the one and only State.
     * @param  context ignored.
     * @return list with one and only state.
     */
    @Override
    protected List<State> getStates(Object context) {
        ArrayList<State> states = new ArrayList<State>();
        states.add(getState());
        return states;
    }


    /**
     * Get the "current" state (there is but one).
     * @param cc ignored.
     * @return the "current" (only possible) state.
     */
    @Override
    public State getCurrentState(Object cc) {
        return getState();
    }


    /**
     * Get the only possible state.
     * @return the state.
     */
    protected State getState() {
        return getState(null, null);
    }


    /**
     * Get the state.
     * @param context ignored.
     * @param stateID ignored.
     * @return the state.
     */
    @Override
    protected State getState(Object context, String stateID) {
        return (state != null)
            ? state
            : spawnState();
    }


    /**
     * Called via setup. Overridden to avoid cloning all data.
     *
     * @param artifact The master-artifact.
     */
    @Override
    protected void initialize(
        Artifact artifact,
        Object context,
        CallMeta meta)
    {
        logger.debug("initialize");
    }


    /** Get the db-unbound flow velocity measurement value with given
     * id. */
    public FlowVelocityMeasurementValue.FastFlowVelocityMeasurementValue
        getFlowVelocityMeasurementValue()
    {
        return FlowVelocityMeasurementFactory.getFlowVelocityMeasurement(
            Integer.parseInt(getDataAsString(DATA_NAME)));
    }
}
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