classdescriptorupdatemethodresolver.java

Java的面向对象数据库系统的源代码

// You can redistribute this software and/or modify it under the terms of
// the Ozone Library License version 1 published by ozone-db.org.
//
// The original code and portions created by SMB are
// Copyright (C) 1997-@year@ by SMB GmbH. All rights reserved.
//
// $Id: ClassDescriptorUpdateMethodResolver.java,v 1.3 2003/11/27 19:30:08 per_nyfelt Exp $
package org.ozoneDB.tools.OPP.srcgen.resolve;

import org.exolab.castor.xml.MarshalException;
import org.exolab.castor.xml.ValidationException;
import org.ozoneDB.tools.OPP.srcgen.MethodResolver;
import org.ozoneDB.tools.OPP.srcgen.ResolverException;
import org.ozoneDB.tools.OPP.srcgen.streamfactory.InputStreamFactory;
import org.ozoneDB.tools.OPP.castor.Methods;
import org.ozoneDB.tools.OPP.castor.OzoneClassDescriptor;
import org.ozoneDB.tools.OPP.castor.PublicMethod;
import org.ozoneDB.tools.OPP.message.MessageWriter;
import org.ozoneDB.tools.OPP.CDHelper;
import org.ozoneDB.core.Lock;
import org.xml.sax.InputSource;

import java.io.InputStream;
import java.io.IOException;
import java.util.Map;
import java.util.HashMap;

/**
 * Resolves update methods by reading a class descriptor.
 * @author Joakim Ohlrogge
 * To change this template use Options | File Templates.
 */
public class ClassDescriptorUpdateMethodResolver implements MethodResolver {
    private final String WRITELOCK = "WRITE";
    private final String UPGRADELOCK = "UPGRADE";
    private final String READLOCK = "READ";
    //private final String MAXLOCK = "MAX";
    private final String NONELOCK = "NONE";
    private InputStreamFactory factory;
    private MessageWriter msgListener;


    public ClassDescriptorUpdateMethodResolver(InputStreamFactory factory, MessageWriter msgListener) {
        this.factory = factory;
        this.msgListener = msgListener;
    }

    public void resolveMethods(String className, MethodResolver.UpdateMethodBag result) throws ResolverException {
        try {
            searchUpdateMethods(className, result);
        } catch (ValidationException e) {
            throw new ResolverException(e);
        } catch (MarshalException e) {
            throw new ResolverException(e);
        } catch (IOException e) {
            // This means that the OCD was not found, no error
            msgListener.info("No ocd was found!");
            msgListener.debug("message: " + e.getMessage());
        }


    }

    /**
     * Try to load the XML class descriptor to...
     */
    private void searchUpdateMethods(String className, MethodResolver.UpdateMethodBag updateMethods) throws ValidationException, MarshalException, IOException {
        OzoneClassDescriptor descriptor = null;
        InputStream input = factory.newInstance(className);
        descriptor = CDHelper.xml2Descriptor(new InputSource(input));

        Methods mths = descriptor.getMethods();
        PublicMethod[] m = mths.getPublicMethod();
        for (int i = 0; i < m.length; i++) {
            String methodName = m[i].getName();
            String locklevel = m[i].getLocklevel();

            int level = stringToLockLevel(locklevel);


            boolean isUpdate = level > Lock.LEVEL_READ;
/*            if (isUpdate && updateMethods.keySet().contains(methodName)) {
                int oldlevel = ((Integer)updateMethods.get(methodName)).intValue();
                if (oldlevel < level){
                    msgListener.info("'"+methodName+"' has already been marked with a weaker lock level");
                    msgListener.info("Upgrading '"+methodName+"' from level "+oldlevel+" to level "+ level);
                    updateMethods.put(methodName, new Integer(level));
                }
                msgListener.warning("All '" + methodName + "' methods will be marked as update methods.");
            }*/
            if (isUpdate) {
                updateMethods.addMethod(methodName, level);
            }
        }
    }

    private int stringToLockLevel(String level) {
        if (WRITELOCK.equals(level)) {
            return Lock.LEVEL_WRITE;
        } else if (UPGRADELOCK.equals(level)) {
            return Lock.LEVEL_UPGRADE;
        } else if (READLOCK.equals(level)) {
            return Lock.LEVEL_READ;
        } else if (NONELOCK.equals(level)) {
            return Lock.LEVEL_NONE;
        }
        return Lock.LEVEL_READ;
    }
}