bundles/org.eclipse.osgi/core/framework/org/eclipse/osgi/framework/internal/core/FilterImpl.java

/*******************************************************************************
 * Copyright (c) 2003, 2005 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.osgi.framework.internal.core;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Dictionary;
import java.util.Iterator;

import org.eclipse.osgi.framework.debug.Debug;
import org.eclipse.osgi.framework.util.Headers;
import org.eclipse.osgi.util.NLS;
import org.osgi.framework.Filter;
import org.osgi.framework.InvalidSyntaxException;

/**
 * RFC 1960-based Filter. Filter objects can be created by calling
 * the constructor with the desired filter string.
 * A Filter object can be called numerous times to determine if the
 * match argument matches the filter string that was used to create the Filter
 * object.
 *
 * <p>The syntax of a filter string is the string representation
 * of LDAP search filters as defined in RFC 1960:
 * <i>A String Representation of LDAP Search Filters</i> (available at
 * http://www.ietf.org/rfc/rfc1960.txt).
 * It should be noted that RFC 2254:
 * <i>A String Representation of LDAP Search Filters</i>
 * (available at http://www.ietf.org/rfc/rfc2254.txt) supersedes
 * RFC 1960 but only adds extensible matching and is not applicable for this
 * API.
 *
 * <p>The string representation of an LDAP search filter is defined by the
 * following grammar. It uses a prefix format.
 * <pre>
 *   &lt;filter&gt; ::= '(' &lt;filtercomp&gt; ')'
 *   &lt;filtercomp&gt; ::= &lt;and&gt; | &lt;or&gt; | &lt;not&gt; | &lt;item&gt;
 *   &lt;and&gt; ::= '&' &lt;filterlist&gt;
 *   &lt;or&gt; ::= '|' &lt;filterlist&gt;
 *   &lt;not&gt; ::= '!' &lt;filter&gt;
 *   &lt;filterlist&gt; ::= &lt;filter&gt; | &lt;filter&gt; &lt;filterlist&gt;
 *   &lt;item&gt; ::= &lt;simple&gt; | &lt;present&gt; | &lt;substring&gt;
 *   &lt;simple&gt; ::= &lt;attr&gt; &lt;filtertype&gt; &lt;value&gt;
 *   &lt;filtertype&gt; ::= &lt;equal&gt; | &lt;approx&gt; | &lt;greater&gt; | &lt;less&gt;
 *   &lt;equal&gt; ::= '='
 *   &lt;approx&gt; ::= '~='
 *   &lt;greater&gt; ::= '&gt;='
 *   &lt;less&gt; ::= '&lt;='
 *   &lt;present&gt; ::= &lt;attr&gt; '=*'
 *   &lt;substring&gt; ::= &lt;attr&gt; '=' &lt;initial&gt; &lt;any&gt; &lt;final&gt;
 *   &lt;initial&gt; ::= NULL | &lt;value&gt;
 *   &lt;any&gt; ::= '*' &lt;starval&gt;
 *   &lt;starval&gt; ::= NULL | &lt;value&gt; '*' &lt;starval&gt;
 *   &lt;final&gt; ::= NULL | &lt;value&gt;
 * </pre>
 *
 * <code>&lt;attr&gt;</code> is a string representing an attribute, or
 * key, in the properties objects of the registered services.
 * Attribute names are not case sensitive;
 * that is cn and CN both refer to the same attribute.
 * <code>&lt;value&gt;</code> is a string representing the value, or part of
 * one, of a key in the properties objects of the registered services.
 * If a <code>&lt;value&gt;</code> must
 * contain one of the characters '<code>*</code>' or '<code>(</code>'
 * or '<code>)</code>', these characters
 * should be escaped by preceding them with the backslash '<code>\</code>'
 * character.
 * Note that although both the <code>&lt;substring&gt;</code> and
 * <code>&lt;present&gt;</code> productions can
 * produce the <code>'attr=*'</code> construct, this construct is used only to
 * denote a presence filter.
 *
 * <p>Examples of LDAP filters are:
 *
 * <pre>
 *   &quot;(cn=Babs Jensen)&quot;
 *   &quot;(!(cn=Tim Howes))&quot;
 *   &quot;(&(&quot; + Constants.OBJECTCLASS + &quot;=Person)(|(sn=Jensen)(cn=Babs J*)))&quot;
 *   &quot;(o=univ*of*mich*)&quot;
 * </pre>
 *
 * <p>The approximate match (<code>~=</code>) is implementation specific but
 * should at least ignore case and white space differences. Optional are
 * codes like soundex or other smart "closeness" comparisons.
 *
 * <p>Comparison of values is not straightforward. Strings
 * are compared differently than numbers and it is
 * possible for a key to have multiple values. Note that
 * that keys in the match argument must always be strings.
 * The comparison is defined by the object type of the key's
 * value. The following rules apply for comparison:
 *
 * <blockquote>
 * <TABLE BORDER=0>
 * <TR><TD><b>Property Value Type </b></TD><TD><b>Comparison Type</b></TD></TR>
 * <TR><TD>String </TD><TD>String comparison</TD></TR>
 * <TR valign=top><TD>Integer, Long, Float, Double, Byte, Short, BigInteger, BigDecimal </TD><TD>numerical comparison</TD></TR>
 * <TR><TD>Character </TD><TD>character comparison</TD></TR>
 * <TR><TD>Boolean </TD><TD>equality comparisons only</TD></TR>
 * <TR><TD>[] (array)</TD><TD>recursively applied to values </TD></TR>
 * <TR><TD>Vector</TD><TD>recursively applied to elements </TD></TR>
 * </TABLE>
 * Note: arrays of primitives are also supported.
 * </blockquote>
 *
 * A filter matches a key that has multiple values if it
 * matches at least one of those values. For example,
 * <pre>
 *   Dictionary d = new Hashtable();
 *   d.put( "cn", new String[] { "a", "b", "c" } );
 * </pre>
 *   d will match <code>(cn=a)</code> and also <code>(cn=b)</code>
 *
 * <p>A filter component that references a key having an unrecognizable
 * data type will evaluate to <code>false</code> .
 */

public class FilterImpl implements Filter /* since Framework 1.1 */{
	/* public methods in org.osgi.framework.Filter */

	/**
	 * Constructs a {@link FilterImpl} object. This filter object may be used
	 * to match a {@link ServiceReferenceImpl} or a Dictionary.
	 *
	 * <p> If the filter cannot be parsed, an {@link InvalidSyntaxException}
	 * will be thrown with a human readable message where the
	 * filter became unparsable.
	 *
	 * @param filter the filter string.
	 * @exception InvalidSyntaxException If the filter parameter contains
	 * an invalid filter string that cannot be parsed.
	 */
	public FilterImpl(String filter) throws InvalidSyntaxException {
		topLevel = true;
		new Parser(filter).parse(this);
	}

	/**
	 * Filter using a service's properties.
	 * The Filter is executed using the referenced service's
	 * properties.
	 *
	 * @param reference the reference to the service whose
	 * properties are used in the match.
	 * @return <code>true</code> if the service's properties match this filter;
	 * <code>false</code> otherwise.
	 */
	public boolean match(org.osgi.framework.ServiceReference reference) {
		return match0(((ServiceReferenceImpl) reference).registration.properties);
	}

	/**
	 * Filter using a Dictionary.
	 * The Filter is executed using the Dictionary's keys.
	 *
	 * @param dictionary the dictionary whose keys are used in the match.
	 * @return <code>true</code> if the Dictionary's keys match this filter;
	 * <code>false</code> otherwise.
	 */
	public boolean match(Dictionary dictionary) {
		if (dictionary != null) {
			dictionary = new Headers(dictionary);
		}

		return match0(dictionary);
	}

	/**
	 * Filter with case sensitivity using a <tt>Dictionary</tt> object. The
	 * Filter is executed using the <tt>Dictionary</tt> object's keys and
	 * values. The keys are case sensitivley matched with the filter.
	 * 
	 * @param dictionary The <tt>Dictionary</tt> object whose keys are used in
	 *        the match.
	 * 
	 * @return <tt>true</tt> if the <tt>Dictionary</tt> object's keys and
	 *         values match this filter; <tt>false</tt> otherwise.
	 * 
	 * @since 1.3
	 */
	public boolean matchCase(Dictionary dictionary) {
		return match0(dictionary);
	}

	/**
	 * Returns this Filter object's filter string.
	 * The filter string is normalized by removing
	 * whitespace which does not affect the meaning of the filter.
	 *
	 * @return filter string.
	 */
	public String toString() {
		if (this.filter == null) {
			StringBuffer filter = new StringBuffer();
			filter.append('(');

			switch (operation) {
				case AND :
					{
						filter.append('&');

						FilterImpl[] filters = (FilterImpl[]) value;
						int size = filters.length;

						for (int i = 0; i < size; i++) {
							filter.append(filters[i].toString());
						}

						break;
					}

				case OR :
					{
						filter.append('|');

						FilterImpl[] filters = (FilterImpl[]) value;
						int size = filters.length;

						for (int i = 0; i < size; i++) {
							filter.append(filters[i].toString());
						}

						break;
					}

				case NOT :
					{
						filter.append('!');
						filter.append(value.toString());

						break;
					}

				case SUBSTRING :
					{
						filter.append(attr);
						filter.append('=');

						String[] substrings = (String[]) value;

						int size = substrings.length;

						for (int i = 0; i < size; i++) {
							String substr = substrings[i];

							if (substr == null) /* * */{
								filter.append('*');
							} else /* xxx */{
								filter.append(encodeValue(substr));
							}
						}

						break;
					}
				case EQUAL :
					{
						filter.append(attr);
						filter.append('=');
						filter.append(encodeValue(value.toString()));

						break;
					}
				case GREATER :
					{
						filter.append(attr);
						filter.append(">="); //$NON-NLS-1$
						filter.append(encodeValue(value.toString()));

						break;
					}
				case LESS :
					{
						filter.append(attr);
						filter.append("<="); //$NON-NLS-1$
						filter.append(encodeValue(value.toString()));

						break;
					}
				case APPROX :
					{
						filter.append(attr);
						filter.append("~="); //$NON-NLS-1$
						filter.append(encodeValue(approxString(value.toString())));

						break;
					}

				case PRESENT :
					{
						filter.append(attr);
						filter.append("=*"); //$NON-NLS-1$

						break;
					}
			}

			filter.append(')');

			if (topLevel) /* only hold onto String object at toplevel */{
				this.filter = filter.toString();
			} else {
				return filter.toString();
			}
		}

		return this.filter;
	}

	/**
	 * Compares this Filter object to another object.
	 *
	 * @param obj the object to compare.
	 * @return If the other object is a Filter object, then
	 * returns <code>this.toString().equals(obj.toString())</code>,
	 * otherwise <code>false</code>.
	 */
	public boolean equals(Object obj) {
		if (obj == this) {
			return true;
		}

		if (!(obj instanceof FilterImpl)) {
			return false;
		}

		return this.toString().equals(obj.toString());
	}

	/**
	 * Returns the hashCode for this Filter object.
	 *
	 * @return The hashCode of the filter string, <i>i.e.</i>
	 * <code>this.toString().hashCode()</code>.
	 */
	public int hashCode() {
		return this.toString().hashCode();
	}

	/* Protected fields and methods for the Filter implementation */

	/** filter operation */
	protected int operation;
	protected static final int EQUAL = 1;
	protected static final int APPROX = 2;
	protected static final int GREATER = 3;
	protected static final int LESS = 4;
	protected static final int PRESENT = 5;
	protected static final int SUBSTRING = 6;
	protected static final int AND = 7;
	protected static final int OR = 8;
	protected static final int NOT = 9;

	/** filter attribute or null if operation AND, OR or NOT */
	protected String attr;
	/** filter operands */
	protected Object value;

	/* normalized filter string for topLevel Filter object */
	protected String filter;

	/* true if root Filter object */
	protected boolean topLevel;

	protected FilterImpl() {
		topLevel = false;
	}

	protected void setFilter(int operation, String attr, Object value) {
		this.operation = operation;
		this.attr = attr;
		this.value = value;
	}

	/**
	 * Filter using a service's properties.
	 * The Filter is executed using the referenced service's
	 * properties.
	 *
	 * @param reference A reference to the service whose
	 * properties are used in the match.
	 * @return If the service's properties match the filter,
	 * return <code>true</code>. Otherwise, return <code>false</code>.
	 */
	protected boolean match(ServiceReferenceImpl reference) {
		return match0(reference.registration.properties);
	}

	/**
	 * Internal match routine.
	 * Dictionary parameter must support case-insensitive get.
	 *
	 * @param properties A dictionary whose
	 * keys are used in the match.
	 * @return If the Dictionary's keys match the filter,
	 * return <code>true</code>. Otherwise, return <code>false</code>.
	 */
	protected boolean match0(Dictionary properties) {
		switch (operation) {
			case AND :
				{
					FilterImpl[] filters = (FilterImpl[]) value;
					int size = filters.length;

					for (int i = 0; i < size; i++) {
						if (!filters[i].match0(properties)) {
							return false;
						}
					}

					return true;
				}

			case OR :
				{
					FilterImpl[] filters = (FilterImpl[]) value;
					int size = filters.length;

					for (int i = 0; i < size; i++) {
						if (filters[i].match0(properties)) {
							return true;
						}
					}

					return false;
				}

			case NOT :
				{
					FilterImpl filter = (FilterImpl) value;

					return !filter.match0(properties);
				}

			case SUBSTRING :
			case EQUAL :
			case GREATER :
			case LESS :
			case APPROX :
				{
					Object prop = (properties == null) ? null : properties.get(attr);

					return compare(operation, prop, value);
				}

			case PRESENT :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("PRESENT(" + attr + ")"); //$NON-NLS-1$ //$NON-NLS-2$
					}

					Object prop = (properties == null) ? null : properties.get(attr);

					return prop != null;
				}
		}

		return false;
	}

	/**
	 * Encode the value string such that '(', '*', ')'
	 * and '\' are escaped.
	 *
	 * @param value unencoded value string.
	 * @return encoded value string.
	 */
	protected static String encodeValue(String value) {
		boolean encoded = false;
		int inlen = value.length();
		int outlen = inlen << 1; /* inlen * 2 */

		char[] output = new char[outlen];
		value.getChars(0, inlen, output, inlen);

		int cursor = 0;
		for (int i = inlen; i < outlen; i++) {
			char c = output[i];

			switch (c) {
				case '(' :
				case '*' :
				case ')' :
				case '\\' :
					{
						output[cursor] = '\\';
						cursor++;
						encoded = true;

						break;
					}
			}

			output[cursor] = c;
			cursor++;
		}

		return encoded ? new String(output, 0, cursor) : value;
	}

	protected boolean compare(int operation, Object value1, Object value2) {
		if (value1 == null) {
			if (Debug.DEBUG && Debug.DEBUG_FILTER) {
				Debug.println("compare(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
			}

			return false;
		}

		if (value1 instanceof String) {
			return compare_String(operation, (String) value1, value2);
		}

		Class clazz = value1.getClass();

		if (clazz.isArray()) {
			Class type = clazz.getComponentType();

			if (type.isPrimitive()) {
				return compare_PrimitiveArray(operation, type, value1, value2);
			} else {
				return compare_ObjectArray(operation, (Object[]) value1, value2);
			}
		}

		if (value1 instanceof Collection) {
			return compare_Collection(operation, (Collection) value1, value2);
		}

		if (value1 instanceof Integer) {
			return compare_Integer(operation, ((Integer) value1).intValue(), value2);
		}

		if (value1 instanceof Long) {
			return compare_Long(operation, ((Long) value1).longValue(), value2);
		}

		if (value1 instanceof Byte) {
			return compare_Byte(operation, ((Byte) value1).byteValue(), value2);
		}

		if (value1 instanceof Short) {
			return compare_Short(operation, ((Short) value1).shortValue(), value2);
		}

		if (value1 instanceof Character) {
			return compare_Character(operation, ((Character) value1).charValue(), value2);
		}

		if (value1 instanceof Float) {
			return compare_Float(operation, ((Float) value1).floatValue(), value2);
		}

		if (value1 instanceof Double) {
			return compare_Double(operation, ((Double) value1).doubleValue(), value2);
		}

		if (value1 instanceof Boolean) {
			return compare_Boolean(operation, ((Boolean) value1).booleanValue(), value2);
		}

		if (value1 instanceof Comparable) {
			return compare_Comparable(operation, (Comparable) value1, value2);
		}
		
		return compare_Unknown(operation, value1, value2);	// RFC 59
	}

	protected boolean compare_Collection(int operation, Collection collection, Object value2) {
		Iterator iterator = collection.iterator();

		while (iterator.hasNext()) {
			if (compare(operation, iterator.next(), value2)) {
				return true;
			}
		}

		return false;
	}

	protected boolean compare_ObjectArray(int operation, Object[] array, Object value2) {
		int size = array.length;

		for (int i = 0; i < size; i++) {
			if (compare(operation, array[i], value2)) {
				return true;
			}
		}

		return false;
	}

	protected boolean compare_PrimitiveArray(int operation, Class type, Object primarray, Object value2) {
		if (Integer.TYPE.isAssignableFrom(type)) {
			int[] array = (int[]) primarray;

			int size = array.length;

			for (int i = 0; i < size; i++) {
				if (compare_Integer(operation, array[i], value2)) {
					return true;
				}
			}

			return false;
		}

		if (Long.TYPE.isAssignableFrom(type)) {
			long[] array = (long[]) primarray;

			int size = array.length;

			for (int i = 0; i < size; i++) {
				if (compare_Long(operation, array[i], value2)) {
					return true;
				}
			}

			return false;
		}

		if (Byte.TYPE.isAssignableFrom(type)) {
			byte[] array = (byte[]) primarray;

			int size = array.length;

			for (int i = 0; i < size; i++) {
				if (compare_Byte(operation, array[i], value2)) {
					return true;
				}
			}

			return false;
		}

		if (Short.TYPE.isAssignableFrom(type)) {
			short[] array = (short[]) primarray;

			int size = array.length;

			for (int i = 0; i < size; i++) {
				if (compare_Short(operation, array[i], value2)) {
					return true;
				}
			}

			return false;
		}

		if (Character.TYPE.isAssignableFrom(type)) {
			char[] array = (char[]) primarray;

			int size = array.length;

			for (int i = 0; i < size; i++) {
				if (compare_Character(operation, array[i], value2)) {
					return true;
				}
			}

			return false;
		}

		if (Float.TYPE.isAssignableFrom(type)) {
			float[] array = (float[]) primarray;

			int size = array.length;

			for (int i = 0; i < size; i++) {
				if (compare_Float(operation, array[i], value2)) {
					return true;
				}
			}

			return false;
		}

		if (Double.TYPE.isAssignableFrom(type)) {
			double[] array = (double[]) primarray;

			int size = array.length;

			for (int i = 0; i < size; i++) {
				if (compare_Double(operation, array[i], value2)) {
					return true;
				}
			}

			return false;
		}

		if (Boolean.TYPE.isAssignableFrom(type)) {
			boolean[] array = (boolean[]) primarray;

			int size = array.length;

			for (int i = 0; i < size; i++) {
				if (compare_Boolean(operation, array[i], value2)) {
					return true;
				}
			}

			return false;
		}

		return false;
	}

	protected boolean compare_String(int operation, String string, Object value2) {
		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + string + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
		
					String[] substrings = (String[]) value2;
					int pos = 0;
		
					int size = substrings.length;
		
					for (int i = 0; i < size; i++) {
						String substr = substrings[i];
		
						if (i + 1 < size) /* if this is not that last substr */{
							if (substr == null) /* * */{
								String substr2 = substrings[i + 1];
		
								if (substr2 == null) /* ** */
									continue; /* ignore first star */
								/* *xxx */
								if (Debug.DEBUG && Debug.DEBUG_FILTER) {
									Debug.println("indexOf(\"" + substr2 + "\"," + pos + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
								}
								int index = string.indexOf(substr2, pos);
								if (index == -1) {
									return false;
								}
		
								pos = index + substr2.length();
								if (i + 2 < size) // if there are more substrings, increment over the string we just matched; otherwise need to do the last substr check
									i++;
							} else /* xxx */{
								int len = substr.length();
		
								if (Debug.DEBUG && Debug.DEBUG_FILTER) {
									Debug.println("regionMatches(" + pos + ",\"" + substr + "\")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
								}
								if (string.regionMatches(pos, substr, 0, len)) {
									pos += len;
								} else {
									return false;
								}
							}
						} else /* last substr */{
							if (substr == null) /* * */{
								return true;
							} else /* xxx */{
								if (Debug.DEBUG && Debug.DEBUG_FILTER) {
									Debug.println("regionMatches(" + pos + "," + substr + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
								}
								return string.endsWith(substr);
							}
						}
					}
		
					return true;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + string + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return string.equals(value2);
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + string + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}

					string = approxString(string);
					String string2 = approxString((String) value2);

					return string.equalsIgnoreCase(string2);
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + string + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return string.compareTo((String) value2) >= 0;
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + string + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return string.compareTo((String) value2) <= 0;
				}
		}

		return false;
	}

	protected boolean compare_Integer(int operation, int intval, Object value2) {
		int intval2 = Integer.parseInt(((String) value2).trim());

		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + intval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return false;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + intval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return intval == intval2;
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + intval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return intval == intval2;
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + intval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return intval >= intval2;
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + intval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return intval <= intval2;
				}
		}

		return false;
	}

	protected boolean compare_Long(int operation, long longval, Object value2) {
		long longval2 = Long.parseLong(((String) value2).trim());

		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + longval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return false;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + longval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return longval == longval2;
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + longval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return longval == longval2;
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + longval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return longval >= longval2;
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + longval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return longval <= longval2;
				}
		}

		return false;
	}

	protected boolean compare_Byte(int operation, byte byteval, Object value2) {
		byte byteval2 = Byte.parseByte(((String) value2).trim());

		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + byteval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return false;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + byteval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return byteval == byteval2;
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + byteval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return byteval == byteval2;
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + byteval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return byteval >= byteval2;
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + byteval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return byteval <= byteval2;
				}
		}

		return false;
	}

	protected boolean compare_Short(int operation, short shortval, Object value2) {
		short shortval2 = Short.parseShort(((String) value2).trim());

		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + shortval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return false;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + shortval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return shortval == shortval2;
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + shortval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return shortval == shortval2;
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + shortval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return shortval >= shortval2;
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + shortval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return shortval <= shortval2;
				}
		}

		return false;
	}

	protected boolean compare_Character(int operation, char charval, Object value2) {
		char charval2 = (((String) value2).trim()).charAt(0);

		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + charval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return false;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + charval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return charval == charval2;
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + charval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return Character.toLowerCase(charval) == Character.toLowerCase(charval2);
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + charval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return charval >= charval2;
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + charval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return charval <= charval2;
				}
		}

		return false;
	}

	protected boolean compare_Boolean(int operation, boolean boolval, Object value2) {
		boolean boolval2 = new Boolean(((String) value2).trim()).booleanValue();

		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + boolval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return false;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + boolval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return boolval == boolval2;
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + boolval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return boolval == boolval2;
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + boolval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return boolval == boolval2;
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + boolval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return boolval == boolval2;
				}
		}

		return false;
	}

	protected boolean compare_Float(int operation, float floatval, Object value2) {
		float floatval2 = Float.parseFloat(((String) value2).trim());

		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + floatval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return false;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + floatval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return floatval == floatval2;
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + floatval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return floatval == floatval2;
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + floatval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return floatval >= floatval2;
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + floatval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return floatval <= floatval2;
				}
		}

		return false;
	}

	protected boolean compare_Double(int operation, double doubleval, Object value2) {
		double doubleval2 = Double.parseDouble(((String) value2).trim());

		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + doubleval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return false;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + doubleval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return doubleval == doubleval2;
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + doubleval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return doubleval == doubleval2;
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + doubleval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return doubleval >= doubleval2;
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + doubleval + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return doubleval <= doubleval2;
				}
		}

		return false;
	}
	
	protected static final Class[] constructorType = new Class [] {String.class};

	protected boolean compare_Comparable(int operation, Comparable value1, Object value2) {
		Constructor constructor;

		try {
			constructor = value1.getClass().getConstructor(constructorType);
		} 
		catch (NoSuchMethodException e) {
			return false;
		}
		try {
			if (!constructor.isAccessible())
				AccessController.doPrivileged(new SetAccessibleAction(constructor));
			value2 = constructor.newInstance(new Object[] {((String) value2).trim()});
		}
		catch (IllegalAccessException e) {
			return false;
		}
		catch (InvocationTargetException e) {
			return false;
		}
		catch (InstantiationException e) {
			return false;
		}

		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return false;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return value1.compareTo(value2) == 0;
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return value1.compareTo(value2) == 0;
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return value1.compareTo(value2) >= 0;
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return value1.compareTo(value2) <= 0;
				}
		}

		return false;
	}

	protected boolean compare_Unknown(int operation, Object value1, Object value2) { //RFC 59
		Constructor constructor;
		try {
			constructor = value1.getClass().getConstructor(constructorType);
		} 
		catch (NoSuchMethodException e) {
			if (Debug.DEBUG && Debug.DEBUG_FILTER) {
				Debug.println("Type not supported"); //$NON-NLS-1$
			}
			return false;
		}
		try {
			if (!constructor.isAccessible())
				AccessController.doPrivileged(new SetAccessibleAction(constructor));
			value2 = constructor.newInstance(new Object[] {((String) value2).trim()});
		}
		catch (IllegalAccessException e) {
			return false;
		}
		catch (InvocationTargetException e) {
			return false;
		}
		catch (InstantiationException e) {
			return false;
		}
	
		switch (operation) {
			case SUBSTRING :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("SUBSTRING(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return false;
				}
			case EQUAL :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("EQUAL(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return value1.equals(value2);
				}
			case APPROX :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("APPROX(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return value1.equals(value2);
				}
			case GREATER :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("GREATER(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return value1.equals(value2);
				}
			case LESS :
				{
					if (Debug.DEBUG && Debug.DEBUG_FILTER) {
						Debug.println("LESS(" + value1 + "," + value2 + ")"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
					}
					return value1.equals(value2);
				}
		}
	
		return false;
	}

	/**
	 * Map a string for an APPROX (~=) comparison.
	 *
	 * This implementation removes white spaces.
	 * This is the minimum implementation allowed by
	 * the OSGi spec.
	 *
	 * @param input Input string.
	 * @return String ready for APPROX comparison.
	 */
	protected static String approxString(String input) {
		boolean changed = false;
		char[] output = input.toCharArray();

		int length = output.length;

		int cursor = 0;
		for (int i = 0; i < length; i++) {
			char c = output[i];

			if (Character.isWhitespace(c)) {
				changed = true;
				continue;
			}

			output[cursor] = c;
			cursor++;
		}

		return changed ? new String(output, 0, cursor) : input;
	}
	
	/**
	 * Returns the leftmost required objectClass value for the filter to evaluate to true.
	 * 
	 * @return The leftmost required objectClass value or null if none could be determined.
	 */
	public String getRequiredObjectClass() {
		// just checking for simple filters here where objectClass is the only attr or it is one attr of a base '&' clause
		// (objectClass=org.acme.BrickService) OK
		// (&(objectClass=org.acme.BrickService)(|(vendor=IBM)(vendor=SUN))) OK
		// (objectClass=org.acme.*) NOT OK
		// (|(objectClass=org.acme.BrickService)(objectClass=org.acme.CementService)) NOT OK
		// (&(objectClass=org.acme.BrickService)(objectClass=org.acme.CementService)) OK but only the first objectClass is returned
		switch (operation) {
			case EQUAL :
				if (attr.equalsIgnoreCase(org.osgi.framework.Constants.OBJECTCLASS) && (value instanceof String))
					return (String) value;
				break;
			case AND :
				FilterImpl[] clauses = (FilterImpl[]) value;
				for (int i = 0; i < clauses.length; i++)
					if (clauses[i].operation == EQUAL) {
						String result = clauses[i].getRequiredObjectClass();
						if (result != null)
							return result;
					}
				break;
		}
		return null;
	}

	/**
	 * Returns a objectClass filter string for the specified objectClass.
	 * @return A filter string for the specified objectClass or null if the specified objectClass is null.
	 */
	public static String getObjectClassFilterString(String objectClass) {
		if (objectClass == null)
			return null;
		return "(" + org.osgi.framework.Constants.OBJECTCLASS + "=" + objectClass + ")";  //$NON-NLS-1$//$NON-NLS-2$ //$NON-NLS-3$
	}


	/**
	 * Parser class for OSGi filter strings. This class parses
	 * the complete filter string and builds a tree of Filter
	 * objects rooted at the parent.
	 */
	static class Parser {
		protected String filterstring;
		protected char[] filter;
		protected int pos;

		protected Parser(String filterstring) {
			this.filterstring = filterstring;
			filter = filterstring.toCharArray();
			pos = 0;
		}

		protected void parse(FilterImpl parent) throws InvalidSyntaxException {
			try {
				parse_filter(parent);
			} catch (ArrayIndexOutOfBoundsException e) {
				throw new InvalidSyntaxException(Msg.FILTER_TERMINATED_ABRUBTLY, filterstring); 
			}

			if (pos != filter.length) {
				throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_TRAILING_CHARACTERS, String.valueOf(pos)), filterstring); 
			}
		}

		protected void parse_filter(FilterImpl parent) throws InvalidSyntaxException {
			skipWhiteSpace();

			if (filter[pos] != '(') {
				throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_MISSING_LEFTPAREN, String.valueOf(pos)), filterstring); 
			}

			pos++;

			parse_filtercomp(parent);

			skipWhiteSpace();

			if (filter[pos] != ')') {
				throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_MISSING_RIGHTPAREN, String.valueOf(pos)), filterstring); 
			}

			pos++;

			skipWhiteSpace();
		}

		protected void parse_filtercomp(FilterImpl parent) throws InvalidSyntaxException {
			skipWhiteSpace();

			char c = filter[pos];

			switch (c) {
				case '&' :
					{
						pos++;
						parse_and(parent);
						break;
					}
				case '|' :
					{
						pos++;
						parse_or(parent);
						break;
					}
				case '!' :
					{
						pos++;
						parse_not(parent);
						break;
					}
				default :
					{
						parse_item(parent);
						break;
					}
			}
		}

		protected void parse_and(FilterImpl parent) throws InvalidSyntaxException {
			skipWhiteSpace();

			if (filter[pos] != '(') {
				throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_MISSING_LEFTPAREN, String.valueOf(pos)), filterstring); 
			}

			ArrayList operands = new ArrayList(10);

			while (filter[pos] == '(') {
				FilterImpl child = new FilterImpl();
				parse_filter(child);
				operands.add(child);
			}

			int size = operands.size();

			FilterImpl[] children = new FilterImpl[size];

			operands.toArray(children);

			parent.setFilter(FilterImpl.AND, null, children);
		}

		protected void parse_or(FilterImpl parent) throws InvalidSyntaxException {
			skipWhiteSpace();

			if (filter[pos] != '(') {
				throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_MISSING_LEFTPAREN, String.valueOf(pos)), filterstring); 
			}

			ArrayList operands = new ArrayList(10);

			while (filter[pos] == '(') {
				FilterImpl child = new FilterImpl();
				parse_filter(child);
				operands.add(child);
			}

			int size = operands.size();

			FilterImpl[] children = new FilterImpl[size];

			operands.toArray(children);

			parent.setFilter(FilterImpl.OR, null, children);
		}

		protected void parse_not(FilterImpl parent) throws InvalidSyntaxException {
			skipWhiteSpace();

			if (filter[pos] != '(') {
				throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_MISSING_LEFTPAREN, String.valueOf(pos)), filterstring); 
			}

			FilterImpl child = new FilterImpl();
			parse_filter(child);

			parent.setFilter(FilterImpl.NOT, null, child);
		}

		protected void parse_item(FilterImpl parent) throws InvalidSyntaxException {
			String attr = parse_attr();

			skipWhiteSpace();

			switch (filter[pos]) {
				case '~' :
					{
						if (filter[pos + 1] == '=') {
							pos += 2;
							parent.setFilter(FilterImpl.APPROX, attr, parse_value());
							return;
						}
						break;
					}
				case '>' :
					{
						if (filter[pos + 1] == '=') {
							pos += 2;
							parent.setFilter(FilterImpl.GREATER, attr, parse_value());
							return;
						}
						break;
					}
				case '<' :
					{
						if (filter[pos + 1] == '=') {
							pos += 2;
							parent.setFilter(FilterImpl.LESS, attr, parse_value());
							return;
						}
						break;
					}
				case '=' :
					{
						if (filter[pos + 1] == '*') {
							int oldpos = pos;
							pos += 2;
							skipWhiteSpace();
							if (filter[pos] == ')') {
								parent.setFilter(FilterImpl.PRESENT, attr, null);
								return; /* present */
							}
							pos = oldpos;
						}

						pos++;
						Object string = parse_substring();

						if (string instanceof String) {
							parent.setFilter(FilterImpl.EQUAL, attr, string);
						} else {
							parent.setFilter(FilterImpl.SUBSTRING, attr, string);
						}

						return;
					}
			}

			throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_INVALID_OPERATOR, String.valueOf(pos)), filterstring); 
		}

		protected String parse_attr() throws InvalidSyntaxException {
			skipWhiteSpace();

			int begin = pos;
			int end = pos;

			char c = filter[pos];

			while ("~<>=()".indexOf(c) == -1) { //$NON-NLS-1$
				pos++;

				if (!Character.isWhitespace(c)) {
					end = pos;
				}

				c = filter[pos];
			}

			int length = end - begin;

			if (length == 0) {
				throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_MISSING_ATTR, String.valueOf(pos)), filterstring); 
			}

			return new String(filter, begin, length);
		}

		protected String parse_value() throws InvalidSyntaxException {
			StringBuffer sb = new StringBuffer(filter.length - pos);

			parseloop: while (true) {
				char c = filter[pos];

				switch (c) {
					case ')' :
						{
							break parseloop;
						}

					case '(' :
						{
							throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_INVALID_VALUE, String.valueOf(pos)), filterstring); 
						}

					case '\\' :
						{
							pos++;
							c = filter[pos];
							/* fall through into default */
						}

					default :
						{
							sb.append(c);
							pos++;
							break;
						}
				}
			}

			if (sb.length() == 0) {
				throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_MISSING_VALUE, String.valueOf(pos)), filterstring); 
			}

			return sb.toString();
		}

		protected Object parse_substring() throws InvalidSyntaxException {
			StringBuffer sb = new StringBuffer(filter.length - pos);

			ArrayList operands = new ArrayList(10);

			parseloop: while (true) {
				char c = filter[pos];

				switch (c) {
					case ')' :
						{
							if (sb.length() > 0) {
								operands.add(sb.toString());
							}

							break parseloop;
						}

					case '(' :
						{
							throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_INVALID_VALUE, String.valueOf(pos)), filterstring); 
						}

					case '*' :
						{
							if (sb.length() > 0) {
								operands.add(sb.toString());
							}

							sb.setLength(0);

							operands.add(null);
							pos++;

							break;
						}

					case '\\' :
						{
							pos++;
							c = filter[pos];
							/* fall through into default */
						}

					default :
						{
							sb.append(c);
							pos++;
							break;
						}
				}
			}

			int size = operands.size();

			if (size == 0) {
				throw new InvalidSyntaxException(NLS.bind(Msg.FILTER_MISSING_VALUE, String.valueOf(pos)), filterstring); 
			}

			if (size == 1) {
				Object single = operands.get(0);

				if (single != null) {
					return single;
				}
			}

			String[] strings = new String[size];

			operands.toArray(strings);

			return strings;
		}

		protected void skipWhiteSpace() {
			int length = filter.length;

			while ((pos < length) && Character.isWhitespace(filter[pos])) {
				pos++;
			}
		}
	}

	static class SetAccessibleAction implements PrivilegedAction {
		private Constructor constructor;
		public SetAccessibleAction(Constructor constructor) {
			this.constructor = constructor;
		}
		public Object run() {
			constructor.setAccessible(true);
			return null;
		}
	}
}