apitools/org.eclipse.pde.api.tools/src/org/eclipse/pde/api/tools/internal/provisional/RestrictionModifiers.java

/*******************************************************************************
 * Copyright (c) 2007, 2009 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.pde.api.tools.internal.provisional;

import org.eclipse.pde.api.tools.internal.util.Util;

/**
 * Class containing constants and utility methods for restriction modifiers
 *
 * @since 1.0.0
 */
public final class RestrictionModifiers {

	/**
	 * Restriction kind constant indicating there are no restrictions on a type
	 */
	public static final int NO_RESTRICTIONS = 0x0000;
	/**
	 * Restriction kind constant indicating an interface cannot be implemented
	 */
	public static final int NO_IMPLEMENT = 0x0001;
	/**
	 * Restriction kind constant indicating a type or member cannot be extended.
	 */
	public static final int NO_EXTEND = 0x0002;
	/**
	 * Restriction kind constant indicating a class cannot be instantiated.
	 */
	public static final int NO_INSTANTIATE = 0x0004;
	/**
	 * Restriction kind constant indicating a class cannot have a member
	 * referenced
	 */
	public static final int NO_REFERENCE = 0x0008;
	/**
	 * Restriction kind constant indicating a method cannot be overridden
	 */
	public static final int NO_OVERRIDE = 0x0010;

	/**
	 * Bit mask of all restrictions.
	 */
	public static final int ALL_RESTRICTIONS = 0xFF;

	/**
	 * Constructor no instantiating
	 */
	private RestrictionModifiers() {
	}

	/**
	 * Returns if the no_implement modifier has been set in the specified
	 * modifiers
	 *
	 * @param modifiers the modifiers to resolve
	 * @return if the no_implement modifier has been set in the specified
	 *         modifiers
	 */
	public static final boolean isImplementRestriction(int modifiers) {
		return (modifiers & NO_IMPLEMENT) > 0;
	}

	/**
	 * Returns if the no_extend modifier has been set in the specified modifiers
	 *
	 * @param modifiers the modifiers to resolve
	 * @return if the no_extend modifier has been set in the specified modifiers
	 */
	public static final boolean isExtendRestriction(int modifiers) {
		return (modifiers & NO_EXTEND) > 0;
	}

	/**
	 * Returns if the no_override modifier has been set in the specified
	 * modifiers
	 *
	 * @param modifiers the modifiers to resolve
	 * @return if the no_override modifier has been set in the specified
	 *         modifiers
	 */
	public static final boolean isOverrideRestriction(int modifiers) {
		return (modifiers & NO_OVERRIDE) > 0;
	}

	/**
	 * Returns if the no_instantiate modifier has been set in the specified
	 * modifiers
	 *
	 * @param modifiers the modifiers to resolve
	 * @return if the no_instantiate modifier has been set in the specified
	 *         modifiers
	 */
	public static final boolean isInstantiateRestriction(int modifiers) {
		return (modifiers & NO_INSTANTIATE) > 0;
	}

	/**
	 * Returns if the no_reference modifier has been set in the specified
	 * modifiers
	 *
	 * @param modifiers the modifiers to resolve
	 * @return if the no_reference modifier has been set in the specified
	 *         modifiers
	 */
	public static final boolean isReferenceRestriction(int modifiers) {
		return (modifiers & NO_REFERENCE) > 0;
	}

	/**
	 * Returns if the modifiers indicate no restrictions.
	 *
	 * @param modifiers the modifiers to test
	 * @return if the modifiers indicate no restrictions
	 */
	public static final boolean isUnrestricted(int modifiers) {
		return modifiers == NO_RESTRICTIONS;
	}

	/**
	 * Returns the string representation of the specified restriction(s) or
	 * <code>UNKNOWN_KIND</code> if the kind is unknown.
	 *
	 * @param restrictions the restrictions to get the display string for
	 * @return the string representation for the given restrictions or
	 *         <code>UNKNOWN_KIND</code>
	 * @since 1.0.1
	 */
	public static String getRestrictionText(int restrictions) {
		StringBuilder buffer = new StringBuilder();
		if (restrictions == NO_RESTRICTIONS) {
			return "NO_RESTRICTIONS"; //$NON-NLS-1$
		}
		if (restrictions == ALL_RESTRICTIONS) {
			buffer.append("ALL_RESTRICTIONS"); //$NON-NLS-1$
		} else {
			if ((restrictions & NO_EXTEND) > 0) {
				buffer.append("NO_EXTEND"); //$NON-NLS-1$
			}
			if ((restrictions & NO_IMPLEMENT) > 0) {
				if (buffer.length() > 0) {
					buffer.append(" | "); //$NON-NLS-1$
				}
				buffer.append("NO_IMPLEMENT"); //$NON-NLS-1$
			}
			if ((restrictions & NO_INSTANTIATE) > 0) {
				if (buffer.length() > 0) {
					buffer.append(" | "); //$NON-NLS-1$
				}
				buffer.append("NO_INSTANTIATE"); //$NON-NLS-1$
			}
			if ((restrictions & NO_REFERENCE) > 0) {
				if (buffer.length() > 0) {
					buffer.append(" | "); //$NON-NLS-1$
				}
				buffer.append("NO_REFERENCE"); //$NON-NLS-1$
			}
			if ((restrictions & NO_RESTRICTIONS) > 0) {
				if (buffer.length() > 0) {
					buffer.append(" | "); //$NON-NLS-1$
				}
				buffer.append("NO_RESTRICTIONS"); //$NON-NLS-1$
			}
			if ((restrictions & NO_OVERRIDE) > 0) {
				if (buffer.length() > 0) {
					buffer.append(" | "); //$NON-NLS-1$
				}
				buffer.append("NO_OVERRIDE"); //$NON-NLS-1$
			}
		}
		if (buffer.length() == 0) {
			return Util.UNKNOWN_KIND;
		}
		return buffer.toString();
	}
}