org.nasdanika.cdo.xpath.EMFFunctions.java Source code

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Here is the source code for org.nasdanika.cdo.xpath.EMFFunctions.java

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package org.nasdanika.cdo.xpath;

import java.util.Collection;
import java.util.List;

import org.apache.commons.jxpath.ExpressionContext;
import org.apache.commons.jxpath.NodeSet;
import org.apache.commons.jxpath.Pointer;
import org.eclipse.emf.cdo.CDOObject;
import org.eclipse.emf.ecore.EObject;

/**
 * The initial version of this class was copied from https://github.com/eclipse/eclipse.platform.ui/blob/master/bundles/org.eclipse.e4.emf.xpath/src/org/eclipse/e4/emf/internal/xpath/JXPathContextImpl.java,
 * The original copyright notice is below;
 */
/*******************************************************************************
 * Copyright (c) 2010, 2015 BestSolution.at and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Tom Schindl <tom.schindl@bestsolution.at> - adjustment to EObject
 ******************************************************************************/
public class EMFFunctions {

    /**
     * The original method.
     * @param o
     * @return
     */
    public static String eClassName(Object o) {
        if (o instanceof Collection<?>) {
            if (!((Collection<?>) o).isEmpty()) {
                return eClassName(((Collection<?>) o).iterator().next());
            }
        } else if (o instanceof EObject) {
            return ((EObject) o).eClass().getName();
        } else if (o instanceof NodeSet) {
            List<?> l = ((NodeSet) o).getValues();
            if (l.size() > 0 && l.get(0) instanceof EObject) {
                return eClassName(l.get(0));
            }
        } else if (o instanceof Pointer) {
            if (((Pointer) o).getValue() instanceof EObject) {
                return eClassName(((Pointer) o).getValue());
            }
        }

        return null;
    }

    public static Object iif(boolean condition, Object ifTrue, Object ifFalse) {
        return condition ? ifTrue : ifFalse;
    }

    /**
     * This function can be used to tell new objects from existing objects.
     * In particular, it can be used in 'editable' conditions to make some features editable or not-editable 
     * depending on whether the object is new (create form) or existing. An example of it would be user login
     * or some other unique ID which is not supposed change after object creation. 
     * @param o
     * @return
     */
    public static boolean isTemporary(Object o) {
        return o instanceof CDOObject && ((CDOObject) o).cdoID() != null && ((CDOObject) o).cdoID().isTemporary();
    }

    /**
     * Expression context method.
     * @param expressionContext
     * @return
     */
    public static String eClassName(ExpressionContext expressionContext) {
        Pointer cnp = expressionContext.getContextNodePointer();
        if (cnp != null) {
            Object node = cnp.getNode();
            if (node instanceof EObject) {
                return ((EObject) node).eClass().getName();
            }
        }

        return null;
    }

    /**
     * For checking boolean attributes.  
     * @return
     */
    public static boolean isTrue(Object obj) {
        if (obj instanceof Collection) {
            for (Object e : (Collection<?>) obj) {
                if (isFalse(e)) {
                    return false;
                }
            }
            return true;
        }
        return Boolean.TRUE.equals(obj);
    }

    /**
     * For checking boolean attributes.  
     * @return
     */
    public static boolean isFalse(Object obj) {
        return !isTrue(obj);
    }

    /**
     * Expression context method.
     * @param expressionContext
     * @return
     */
    public static String ePackageNsURI(ExpressionContext expressionContext) {
        Pointer cnp = expressionContext.getContextNodePointer();
        if (cnp != null) {
            Object node = cnp.getNode();
            if (node instanceof EObject) {
                return ((EObject) node).eClass().getEPackage().getNsURI();
            }
        }

        return null;
    }

}