MWDescriptorCopyPolicy.java

/*******************************************************************************
 * Copyright (c) 1998, 2015 Oracle and/or its affiliates. All rights reserved.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.tools.workbench.mappingsmodel.descriptor;

import java.util.List;

import org.eclipse.persistence.tools.workbench.mappingsmodel.MWModel;
import org.eclipse.persistence.tools.workbench.mappingsmodel.ProblemConstants;
import org.eclipse.persistence.tools.workbench.mappingsmodel.handles.MWHandle;
import org.eclipse.persistence.tools.workbench.mappingsmodel.handles.MWMethodHandle;
import org.eclipse.persistence.tools.workbench.mappingsmodel.handles.MWHandle.NodeReferenceScrubber;
import org.eclipse.persistence.tools.workbench.mappingsmodel.meta.MWMethod;
import org.eclipse.persistence.tools.workbench.utility.CollectionTools;
import org.eclipse.persistence.tools.workbench.utility.node.Node;

import org.eclipse.persistence.descriptors.ClassDescriptor;
import org.eclipse.persistence.mappings.converters.ObjectTypeConverter;
import org.eclipse.persistence.oxm.XMLDescriptor;
import org.eclipse.persistence.oxm.mappings.XMLCompositeObjectMapping;
import org.eclipse.persistence.oxm.mappings.XMLDirectMapping;

public final class MWDescriptorCopyPolicy extends MWAbstractDescriptorPolicy {

    private MWMethodHandle methodHandle;

    private volatile String policyType;
        public final static String COPY_POLICY_PROPERTY = "copyPolicy";
        public final static String CLONE = "clone";
        public final static String INSTANTIATION_POLICY = "instantiation";
        public final static String CONSTRUCTOR = "constructor"; // keep
        public final static String CONSTRUCTOR_PROPERTY = CONSTRUCTOR;
        public final static String COPY_POLICY_TYPE_PROPERTY = "copyPolicyType";

        // around for backward compatibility
        public final static String COPY_METHOD_PROPERTY = "copyMethod";


    // ********** constructors **********

    private MWDescriptorCopyPolicy() {
        // for TopLink use only
        super();
    }

    public MWDescriptorCopyPolicy(MWMappingDescriptor descriptor) {
        super(descriptor);
    }


    // ********** initialization **********

    protected void initialize(Node parent) {
        super.initialize(parent);
        this.methodHandle = new MWMethodHandle(this, this.buildMethodScrubber());
        this.policyType = INSTANTIATION_POLICY;
    }


    // ********** accessors **********

    public MWMethod getMethod() {
        return this.methodHandle.getMethod();
    }

    public void setMethod(MWMethod newMethod) {
        MWMethod oldMethod = this.methodHandle.getMethod();
        this.methodHandle.setMethod(newMethod);
        firePropertyChanged(COPY_METHOD_PROPERTY, oldMethod, newMethod);
    }

    public String getPolicyType() {
        return this.policyType;
    }

    public void setPolicyType(String policyType) {
        String oldValue = this.policyType;
        this.policyType = policyType;
        firePropertyChanged(COPY_POLICY_TYPE_PROPERTY, oldValue, this.policyType);
    }


    // ********** containment hierarchy **********

    protected void addChildrenTo(List children) {
        super.addChildrenTo(children);
        children.add(this.methodHandle);
    }

    private NodeReferenceScrubber buildMethodScrubber() {
        return new NodeReferenceScrubber() {
            public void nodeReferenceRemoved(Node node, MWHandle handle) {
                MWDescriptorCopyPolicy.this.setMethod(null);
            }
            public String toString() {
                return "MWDescriptorCopyPolicy.buildMethodScrubber()";
            }
        };
    }


    // ********** MWAbstractDescriptorPolicy implementation **********

    public MWDescriptorPolicy getPersistedPolicy() {
        return this;
    }

    public boolean isActive() {
        return true;
    }


    // ********** runtime conversion **********

    public void adjustRuntimeDescriptor(ClassDescriptor runtimeDescriptor) {
        if (this.policyType == MWDescriptorCopyPolicy.INSTANTIATION_POLICY) {
            runtimeDescriptor.useInstantiationCopyPolicy();

        } else if (this.policyType == MWDescriptorCopyPolicy.CLONE) {
            MWMethod method = getMethod();
            if (method != null) {
                runtimeDescriptor.useCloneCopyPolicy(method.getName());
            }
        }
    }


    // ********** problems **********

    protected void addProblemsTo(List problems) {
        super.addProblemsTo(problems);
        this.checkCloneCopyPolicy(problems);
    }

    private void checkCloneCopyPolicy(List newProblems) {
        if (this.getPolicyType() == CLONE) {
            if (this.getMethod() == null) {
                newProblems.add(this.buildProblem(ProblemConstants.DESCRIPTOR_COPYING_NO_METHOD_SPECIFIED));
            } else {
                if ( ! this.checkIfMethodIsInOwningClass()) {
                    newProblems.add(this.buildProblem(ProblemConstants.DESCRIPTOR_COPYING_METHOD_NOT_VISIBLE));
                }
                else if ( ! this.getMethod().isCandidateCloneMethod()) {
                    newProblems.add(buildProblem(ProblemConstants.DESCRIPTOR_COPYING_METHOD_NOT_VALID));
                }
            }
        }
    }

    public boolean checkIfMethodIsInOwningClass() {
        return CollectionTools.contains(getOwningDescriptor().getMWClass().allMethods(), getMethod());
    }


    // ********** printing **********

    public void toString(StringBuffer sb) {
        sb.append(this.getPolicyType());
        sb.append(", method=");
        sb.append(this.getMethod());
    }


    // ********** TopLink methods **********

    public static XMLDescriptor buildDescriptor() {
        // Same as 5.0 for now
        XMLDescriptor descriptor = new XMLDescriptor();
        descriptor.setJavaClass(MWDescriptorCopyPolicy.class);

        // use an object type mapping so we can preserve object identity
        ObjectTypeConverter policyTypeConverter = new ObjectTypeConverter();
        policyTypeConverter.addConversionValue(
                MWDescriptorCopyPolicy.INSTANTIATION_POLICY,
                MWDescriptorCopyPolicy.INSTANTIATION_POLICY);
        policyTypeConverter.addConversionValue(
                MWDescriptorCopyPolicy.CLONE,
                MWDescriptorCopyPolicy.CLONE);
        // convert the old "constructor" values to "instantiation"
        policyTypeConverter
                .setDefaultAttributeValue(MWDescriptorCopyPolicy.INSTANTIATION_POLICY);
        XMLDirectMapping policyTypeMapping = new XMLDirectMapping();
        policyTypeMapping.setAttributeName("policyType");
        policyTypeMapping.setXPath("policy-type/text()");
        policyTypeMapping.setNullValue(MWDescriptorCopyPolicy.INSTANTIATION_POLICY);
        policyTypeMapping.setConverter(policyTypeConverter);
        descriptor.addMapping(policyTypeMapping);

        XMLCompositeObjectMapping methodHandleMapping = new XMLCompositeObjectMapping();
        methodHandleMapping.setAttributeName("methodHandle");
        methodHandleMapping.setGetMethodName("getMethodHandleForTopLink");
        methodHandleMapping.setSetMethodName("setMethodHandleForTopLink");
        methodHandleMapping.setReferenceClass(MWMethodHandle.class);
        methodHandleMapping.setXPath("copy-policy-method-handle");
        descriptor.addMapping(methodHandleMapping);

        return descriptor;
    }

    /**
     * check for null
     */
    private MWMethodHandle getMethodHandleForTopLink() {
        return (this.methodHandle.getMethod() == null) ? null : this.methodHandle;
    }
    private void setMethodHandleForTopLink(MWMethodHandle handle) {
        NodeReferenceScrubber scrubber = this.buildMethodScrubber();
        this.methodHandle = ((handle == null) ? new MWMethodHandle(this, scrubber) : handle.setScrubber(scrubber));
    }

}