Glassfish example source code file (EJBQLC.java)

This example Glassfish source code file (EJBQLC.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Glassfish tags/keywords

ejbqlexception, ejbqlparser, ejbqlparser, io, jdoqlcodegeneration, log_ejbqlcstartpass, log_ejbqlcstartpass, namemapper, noi18n, noi18n, object, reflection, string, string, tokenbuffer, typesupport, util

The Glassfish EJBQLC.java source code

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 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
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/*
 * EJBQLC.java
 *
 * Created on November 12, 2001
 */

package com.sun.jdo.spi.persistence.support.ejb.ejbqlc;

import java.io.Reader;
import java.io.StringReader;
import java.util.ResourceBundle;
import java.lang.reflect.Method;

import antlr.TokenBuffer;

import org.glassfish.persistence.common.I18NHelper;
import com.sun.jdo.api.persistence.model.Model;
import com.sun.jdo.spi.persistence.support.ejb.model.util.NameMapper;
import com.sun.jdo.spi.persistence.utility.logging.Logger;
import com.sun.jdo.spi.persistence.utility.generator.JavaClassWriterHelper;

/**
 * This class is the driver of the EJBQL compiler. It controls the compiler 
 * passes: syntax analysis, semantic analysis and generation of the JDOQL query.
 * <p>
 * A EJBQLC instance is able to compile multiple EJBQL queries as long as they 
 * come from the same deployement descriptor. The class uses the model instance 
 * passed to the constructor to access any meta data from the deployement 
 * descriptor. Method {@link #compile} compiles a single EJBQL query string 
 * together with the java.lang.reflect.Method instance of the corresponding 
 * finder/selector method. The result is a JDOQLElements instance, that can be 
 * used to construct a JDOQL query instance.
 *
 * @author  Michael Bouschen
 * @author  Shing Wai Chan
 */
public class EJBQLC
{
    /** Meta data access. */
    protected Model model;
    
    /** Name mapping EJB <-> JDO. */
    protected NameMapper nameMapper;
    
    /** The intermediate form of the EJBQL query string. */
    protected EJBQLAST ast;
    
    /** The logger */
    private static Logger logger = LogHelperQueryCompilerEJB.getLogger();
    
    /** I18N support. */
    protected final static ResourceBundle msgs = I18NHelper.loadBundle(
        EJBQLC.class);
        
    /**
     * Signature with CVS keyword substitution for identifying the generated code
     */
    public static final String SIGNATURE = "$RCSfile: EJBQLC.java,v $ $Revision: 1.3 $"; //NOI18N
    
    /**
     * Constructor. 
     * 
     * @param model meta data access.
     * @param nameMapper name mapping EJB <-> JDO.
     */
    public EJBQLC(Model model, NameMapper nameMapper)
    {
        this.model = model;
        this.nameMapper = nameMapper;
    }
    
    /**
     * Compiles the specified query string for the specified 
     * finder/selector method.
     * @param ejbqlQuery the EJBQL query text
     * @param method the Method instance of the finder or selector
     * @param resultTypeMapping result-type-mapping element from the DD
     * @param finderNotSelector <code>true indicates a finder,
     * <code>false a selector
     * @param ejbName the ejb name of the entity bean 
     */
    public JDOQLElements compile(String ejbqlQuery, Method method, 
                                 int resultTypeMapping,
                                 boolean finderNotSelector, String ejbName)
        throws EJBQLException
    {
        boolean finer = logger.isLoggable(Logger.FINER);
        boolean finest = logger.isLoggable(Logger.FINEST);
        if (method == null)
            ErrorMsg.fatal(I18NHelper.getMessage(msgs, 
                "ERR_MissingMethodInstance")); //NOI18N
        if ((ejbqlQuery == null) || ejbqlQuery.trim().length() == 0)
            ErrorMsg.error(I18NHelper.getMessage(msgs, 
                "EXC_MissingEjbqlQueryText", ejbName, //NOI18N
                getMethodSignature(method))); 
        if (finer) 
            logger.finer("LOG_EJBQLCCompile", ejbName, //NOI18N
                         getMethodSignature(method), ejbqlQuery);
                                    
        JDOQLElements result = null;
        TypeSupport typeSupport = new TypeSupport(model, nameMapper);
        ParameterSupport paramSupport = new ParameterSupport(method);
        String pass = null;

        try
        {
            // syntax analysis
            pass = "syntax analysis"; //NOI18N
            if (finer) logger.finer("LOG_EJBQLCStartPass", pass); //NOI18N
            EJBQLParser parser = createStringParser(ejbqlQuery);
            parser.query();
            ast = (EJBQLAST)parser.getAST();
            if (finest) logger.finest("LOG_EJBQLCDumpTree", ast.getTreeRepr("(AST)")); //NOI18N

            // semantic analysis
            pass = "semantic analysis"; //NOI18N
            if (finer) logger.finer("LOG_EJBQLCStartPass", pass); //NOI18N
            Semantic semantic = new Semantic();
            semantic.init(typeSupport, paramSupport, method, resultTypeMapping,
                          finderNotSelector, ejbName);
            semantic.setASTFactory(EJBQLASTFactory.getInstance());
            semantic.query(ast);
            ast = (EJBQLAST)semantic.getAST();
            if (finest) logger.finest("LOG_EJBQLCDumpTree", ast.getTreeRepr("(typed AST)")); //NOI18N

            // JDOQL code generation
            pass = "code generation"; //NOI18N
            if (finer) logger.finer("LOG_EJBQLCStartPass", pass); //NOI18N
            JDOQLCodeGeneration codeGen = new JDOQLCodeGeneration();
            codeGen.init(typeSupport, paramSupport);
            codeGen.setASTFactory(EJBQLASTFactory.getInstance());
            codeGen.query(ast);
            result = codeGen.getJDOQLElements();
            if (finer) logger.finer("LOG_EJBQLCResult", result.toString()); //NOI18N
        }
        catch (EJBQLException ex) {
            // add EJB name, finder/selector, EJBQL to error message.
            Object[] msgArgs = { ejbName, getMethodSignature(method), 
                                 ejbqlQuery, ex.getMessage() };
            ErrorMsg.error(I18NHelper.getMessage(msgs, 
                "EXC_InvalidEJBQLQuery", msgArgs)); //NOI18N
        }
        catch (Throwable t) {
            Object[] msgArgs = { ejbName, getMethodSignature(method), 
                                 ejbqlQuery, t.toString() };
            // log a SEVERE message with nested exception
            ErrorMsg.log(Logger.SEVERE, I18NHelper.getMessage(msgs,
                    "EXC_EJBQLQueryInternalError", msgArgs), t); //NOI18N
        }

        // return the JDOQLElements instance representing the elements 
        // of the JDOQL query.
        return result;
    }

    //========= Internal helper methods ==========
    
    /**
     * Creates an ANTLR EJBQL parser reading a string.
     */
    private EJBQLParser createStringParser(String text)
    {
        Reader in = new StringReader(text);
        EJBQLLexer lexer = new EJBQLLexer(in);
        TokenBuffer buffer = new TokenBuffer(lexer);
        EJBQLParser parser = new EJBQLParser(buffer);
        parser.setASTFactory(EJBQLASTFactory.getInstance());
        return parser;
    }
    
    /** 
     * Returns the signature of a method w/o exceptions and modifiers 
     * as a string.
     */
    private String getMethodSignature(Method m)
    {
        if (m == null) 
            return ""; //NOI18N
        
        return m.getReturnType().getName() + ' ' + m.getName() + 
            JavaClassWriterHelper.parenleft_ +
            JavaClassWriterHelper.getParameterTypesList(m) + 
            JavaClassWriterHelper.parenright_ ;
    }

}