Copyright (c) 2000, 2009 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2009 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.internal.core;

import org.eclipse.jdt.core.IJavaElementDelta;

A simple Java element delta that remembers the kind of changes only.
/**
 * A simple Java element delta that remembers the kind of changes only.
 */
public class SimpleDelta {

	/*
	 * @see IJavaElementDelta#getKind()
	 */
	protected int kind = 0;

	/*
	 * @see IJavaElementDelta#getFlags()
	 */
	protected int changeFlags = 0;

	/*
	 * Marks this delta as added
	 */
	public void added() {
		this.kind = IJavaElementDelta.ADDED;
	}

	/*
	 * Marks this delta as changed with the given change flag
	 */
	public void changed(int flags) {
		this.kind = IJavaElementDelta.CHANGED;
		this.changeFlags |= flags;
	}

	/*
	 * @see IJavaElementDelta#getFlags()
	 */
	public int getFlags() {
		return this.changeFlags;
	}

	/*
	 * @see IJavaElementDelta#getKind()
	 */
	public int getKind() {
		return this.kind;
	}

	/*
	 * Mark this delta has a having a modifiers change
	 */
	public void modifiers() {
		changed(IJavaElementDelta.F_MODIFIERS);
	}

	/*
	 * Marks this delta as removed
	 */
	public void removed() {
		this.kind = IJavaElementDelta.REMOVED;
		this.changeFlags = 0;
	}

	/*
	 * Mark this delta has a having a super type change
	 */
	public void superTypes() {
		changed(IJavaElementDelta.F_SUPER_TYPES);
	}

	protected void toDebugString(StringBuffer buffer) {
		buffer.append("["); //$NON-NLS-1$
		switch (getKind()) {
			case IJavaElementDelta.ADDED :
				buffer.append('+');
				break;
			case IJavaElementDelta.REMOVED :
				buffer.append('-');
				break;
			case IJavaElementDelta.CHANGED :
				buffer.append('*');
				break;
			default :
				buffer.append('?');
				break;
		}
		buffer.append("]: {"); //$NON-NLS-1$
		toDebugString(buffer, getFlags());
		buffer.append("}"); //$NON-NLS-1$
	}

	protected boolean toDebugString(StringBuffer buffer, int flags) {
		boolean prev = false;
		if ((flags & IJavaElementDelta.F_MODIFIERS) != 0) {
			if (prev)
				buffer.append(" | "); //$NON-NLS-1$
			buffer.append("MODIFIERS CHANGED"); //$NON-NLS-1$
			prev = true;
		}
		if ((flags & IJavaElementDelta.F_SUPER_TYPES) != 0) {
			if (prev)
				buffer.append(" | "); //$NON-NLS-1$
			buffer.append("SUPER TYPES CHANGED"); //$NON-NLS-1$
			prev = true;
		}
		return prev;
	}

	@Override
	public String toString() {
		StringBuffer buffer = new StringBuffer();
		toDebugString(buffer);
		return buffer.toString();
	}
}