com.ebay.jetstream.event.processor.esper.EPL.java Source code

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Here is the source code for com.ebay.jetstream.event.processor.esper.EPL.java

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/*
Pulsar
Copyright (C) 2013-2015 eBay Software Foundation
Licensed under the GPL v2 license.  See LICENSE for full terms.
*/
package com.ebay.jetstream.event.processor.esper;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.springframework.beans.factory.InitializingBean;
import org.springframework.jmx.export.annotation.ManagedResource;

import com.ebay.jetstream.config.AbstractNamedBean;
import com.ebay.jetstream.event.JetstreamEvent;
import com.ebay.jetstream.management.Management;
import com.ebay.jetstream.xmlser.Hidden;
import com.ebay.jetstream.xmlser.XSerializable;
import com.espertech.esper.client.EPRuntime;

@ManagedResource(objectName = "Event/Processor", description = "Esper Event Processor Langguage")
public class EPL extends AbstractNamedBean implements Serializable, XSerializable, InitializingBean {

    private static final long serialVersionUID = 1L;

    private final List<String> m_statements = new ArrayList<String>();

    private final List<String> m_statementsWithComments = new ArrayList<String>();

    private List<OnDemandQuery> m_onDemandQueries;

    public void afterPropertiesSet() throws Exception {
        Management.removeBeanOrFolder(getBeanName(), this);
        Management.addBean(getBeanName(), this);
    }

    public List<OnDemandQuery> getOnDemandQueries() {
        return m_onDemandQueries;
    }

    /**
     * Gets the EPL statements as a single string block, such as a CDATA block.
     *
     * @return the set of all statements, in order, each separated by semicolon and new-line.
     */

    public List<String> getEPLStatements() {
        return Collections.unmodifiableList(m_statements);
    }

    /**
     * Gets the list of EPL statements. 
     *
     * @return the list of all statements.
     */
    @Hidden
    public List<String> getStatements() {
        return Collections.unmodifiableList(m_statements);
    }

    public void processOnDemandQueries(EPRuntime runtime, int workerId, JetstreamEvent originalEvent) {
        List<OnDemandQuery> onDemandQueries = getOnDemandQueries();
        if (onDemandQueries != null) {
            for (OnDemandQuery onDemandQuery : onDemandQueries) {
                onDemandQuery.process(runtime, workerId, originalEvent);
            }
        }
    }

    public void setOnDemandQueries(List<OnDemandQuery> onDemandQueries) {
        m_onDemandQueries = onDemandQueries;
        if (onDemandQueries != null) {
            for (OnDemandQuery onDemandQuery : onDemandQueries) {
                if (onDemandQuery == null) {
                    throw new IllegalArgumentException(
                            "onDemandQueries bean must contain at least one 'OnDemandQuery' bean");
                }
                onDemandQuery.validate();
            }
        }
    }

    /**
     * Parses a single String containing a semicolon delimited list of EPL statements.
     *
     * @param statementBlock
     *          the String containing all statements, with each statement separated by a semicolon.
     */

    public void setStatementBlock(String statementBlock) {
        // TODO: better stmt delimiter parsing (e.g. skip ';' in a string or comment)
        m_statements.clear();
        m_statementsWithComments.clear();
        String noncomment = "";

        /**
         * This pattern removes statements with comments. 
         */
        if (statementBlock.contains("/*")) {
            Pattern p = Pattern.compile("/\\*(.*?)\\*/", Pattern.MULTILINE | Pattern.DOTALL);
            Matcher m = p.matcher(statementBlock);
            while (m.find()) {
                noncomment = m.replaceAll("");
            }
        } else {
            noncomment = statementBlock;
        }

        String pattern = "(?s);(?=(?:(?:.*?(?<!\\\\)\"){2})*[^\"]*$)(?=(?:(?:.*?(?<!\\\\)'){2})*[^']*$)";
        String[] stmts = noncomment.split(pattern, -1);
        for (String statement : stmts) {
            String trimmed = statement.trim();
            if (trimmed.length() > 0) {
                m_statements.add(trimmed);
            }
        }
    }

    /**
     * Sets the list of EPL statements.
     *
     * @param statements
     *          the list of EPL statements.
     */
    public void setStatements(List<String> statements) {
        m_statements.clear();
        m_statements.addAll(statements);
    }

}