examples/org.eclipse.ui.examples.readmetool/Eclipse UI Examples Readme Tool/org/eclipse/ui/examples/readmetool/MarkElement.java

package org.eclipse.ui.examples.readmetool;

/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved.
 */
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.ui.views.properties.IPropertySource;
import org.eclipse.ui.model.*;
import org.eclipse.jface.resource.ImageDescriptor;
import java.util.Iterator;
import java.util.Vector;

/**
 * This class represents a marked location in the Readme
 * file text.  
 *
 * TIP: By implementing the <code>IWorkbenchAdapter</code> interface,
 * we can easily add objects of this type to viewers and parts in
 * the workbench.  When a viewer contains <code>IWorkbenchAdapter</code>,
 * the generic <code>WorkbenchContentProvider</code> and
 * <code>WorkbenchLabelProvider</code> can be used to provide
 * navigation and display for that viewer.
 */
public class MarkElement implements IWorkbenchAdapter,IAdaptable {
	private String headingName;
	private IAdaptable parent;
	private int offset;
	private int numberOfLines;
	private int length;
	private Vector children;
/**
 * Creates a new MarkElement and stores parent element and
 * location in the text.
 *
 * @param parent  the parent of this element
 * @param heading text corresponding to the heading
 * @param offset  the offset into the Readme text
 * @param length  the length of the element
 */
public MarkElement(IAdaptable parent, String heading, int offset, int length) {
	this.parent = parent;
	if (parent instanceof MarkElement) {
		((MarkElement)parent).addChild(this);
	}
	this.headingName = heading;
	this.offset = offset;
	this.length = length;
}
/**
 * Adds a child to this element
 */
private void addChild(MarkElement child) {
	if (children == null) {
		children = new Vector();
	}
	children.add(child);
}
/* (non-Javadoc)
 * Method declared on IAdaptable
 */
public Object getAdapter(Class adapter) {
	if (adapter == IWorkbenchAdapter.class)
		return this;
	if (adapter == IPropertySource.class)
		return new MarkElementProperties(this);
	return null;
}
/* (non-Javadoc)
 * Method declared on IWorkbenchAdapter
 */
public Object[] getChildren(Object object) {
	if (children != null) {
		return children.toArray();
	}
	return new Object[0];
}
/* (non-Javadoc)
 * Method declared on IWorkbenchAdapter
 */
public ImageDescriptor getImageDescriptor(Object object) {
	IWorkbenchAdapter parentElement = (IWorkbenchAdapter)parent.getAdapter(IWorkbenchAdapter.class);
	if (parentElement != null) {
		return parentElement.getImageDescriptor(object);
	}
	return null;
}
/* (non-Javadoc)
 * Method declared on IWorkbenchAdapter
 */
public String getLabel(Object o) {
	return headingName;
}
/**
 * Returns the number of characters in this section.
 */
public int getLength() {
	return length;
}
/**
 * Returns the number of lines in the element.
 *
 * @return the number of lines in the element
 */
public int getNumberOfLines() {
	return numberOfLines;
}
/* (non-Javadoc)
 * Method declared on IWorkbenchAdapter
 */
public Object getParent(Object o) {
	return null;
}
/**
 * Returns the offset of this section in the file.
 */
public int getStart() {
	return offset;
}
/**
 * Sets the number of lines in the element
 *
 * @param newNumberOfLines  the number of lines in the element
 */
public void setNumberOfLines(int newNumberOfLines) {
	numberOfLines = newNumberOfLines;
}
}