| /* |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * |
| */ |
| package org.apache.qpid.server.filter; |
| // |
| // Based on like named file from r450141 of the Apache ActiveMQ project <http://www.activemq.org/site/home.html> |
| // |
| |
| import java.math.BigDecimal; |
| import java.util.Collection; |
| import java.util.HashSet; |
| import java.util.Iterator; |
| import java.util.List; |
| |
| import org.apache.qpid.AMQException; |
| import org.apache.qpid.server.queue.Filterable; |
| |
| /** |
| * An expression which performs an operation on two expression values |
| */ |
| public abstract class UnaryExpression<E extends Exception> implements Expression<E> |
| { |
| |
| private static final BigDecimal BD_LONG_MIN_VALUE = BigDecimal.valueOf(Long.MIN_VALUE); |
| protected Expression<E> right; |
| |
| public static<E extends Exception> Expression<E> createNegate(Expression<E> left) |
| { |
| return new NegativeExpression(left); |
| } |
| |
| public static<E extends Exception> BooleanExpression createInExpression(PropertyExpression<E> right, List elements, final boolean not) |
| { |
| |
| // Use a HashSet if there are many elements. |
| Collection t; |
| if (elements.size() == 0) |
| { |
| t = null; |
| } |
| else if (elements.size() < 5) |
| { |
| t = elements; |
| } |
| else |
| { |
| t = new HashSet(elements); |
| } |
| |
| final Collection inList = t; |
| |
| return new InExpression(right, inList, not); |
| } |
| |
| abstract static class BooleanUnaryExpression<E extends Exception> extends UnaryExpression<E> implements BooleanExpression<E> |
| { |
| public BooleanUnaryExpression(Expression<E> left) |
| { |
| super(left); |
| } |
| |
| public boolean matches(Filterable<E> message) throws E |
| { |
| Object object = evaluate(message); |
| |
| return (object != null) && (object == Boolean.TRUE); |
| } |
| } |
| ; |
| |
| public static<E extends Exception> BooleanExpression<E> createNOT(BooleanExpression<E> left) |
| { |
| return new NotExpression(left); |
| } |
| |
| public static BooleanExpression createXPath(final String xpath) |
| { |
| return new XPathExpression(xpath); |
| } |
| |
| public static BooleanExpression createXQuery(final String xpath) |
| { |
| return new XQueryExpression(xpath); |
| } |
| |
| public static<E extends Exception> BooleanExpression createBooleanCast(Expression<E> left) |
| { |
| return new BooleanCastExpression(left); |
| } |
| |
| private static Number negate(Number left) |
| { |
| Class clazz = left.getClass(); |
| if (clazz == Integer.class) |
| { |
| return new Integer(-left.intValue()); |
| } |
| else if (clazz == Long.class) |
| { |
| return new Long(-left.longValue()); |
| } |
| else if (clazz == Float.class) |
| { |
| return new Float(-left.floatValue()); |
| } |
| else if (clazz == Double.class) |
| { |
| return new Double(-left.doubleValue()); |
| } |
| else if (clazz == BigDecimal.class) |
| { |
| // We ussually get a big deciamal when we have Long.MIN_VALUE constant in the |
| // Selector. Long.MIN_VALUE is too big to store in a Long as a positive so we store it |
| // as a Big decimal. But it gets Negated right away.. to here we try to covert it back |
| // to a Long. |
| BigDecimal bd = (BigDecimal) left; |
| bd = bd.negate(); |
| |
| if (BD_LONG_MIN_VALUE.compareTo(bd) == 0) |
| { |
| return new Long(Long.MIN_VALUE); |
| } |
| |
| return bd; |
| } |
| else |
| { |
| throw new RuntimeException("Don't know how to negate: " + left); |
| } |
| } |
| |
| public UnaryExpression(Expression left) |
| { |
| this.right = left; |
| } |
| |
| public Expression<E> getRight() |
| { |
| return right; |
| } |
| |
| public void setRight(Expression expression) |
| { |
| right = expression; |
| } |
| |
| /** |
| * @see java.lang.Object#toString() |
| */ |
| public String toString() |
| { |
| return "(" + getExpressionSymbol() + " " + right.toString() + ")"; |
| } |
| |
| /** |
| * TODO: more efficient hashCode() |
| * |
| * @see java.lang.Object#hashCode() |
| */ |
| public int hashCode() |
| { |
| return toString().hashCode(); |
| } |
| |
| /** |
| * TODO: more efficient hashCode() |
| * |
| * @see java.lang.Object#equals(java.lang.Object) |
| */ |
| public boolean equals(Object o) |
| { |
| |
| if ((o == null) || !this.getClass().equals(o.getClass())) |
| { |
| return false; |
| } |
| |
| return toString().equals(o.toString()); |
| |
| } |
| |
| /** |
| * Returns the symbol that represents this binary expression. For example, addition is |
| * represented by "+" |
| * |
| * @return |
| */ |
| public abstract String getExpressionSymbol(); |
| |
| private static class NegativeExpression<E extends Exception> extends UnaryExpression<E> |
| { |
| public NegativeExpression(final Expression<E> left) |
| { |
| super(left); |
| } |
| |
| public Object evaluate(Filterable<E> message) throws E |
| { |
| Object rvalue = right.evaluate(message); |
| if (rvalue == null) |
| { |
| return null; |
| } |
| |
| if (rvalue instanceof Number) |
| { |
| return negate((Number) rvalue); |
| } |
| |
| return null; |
| } |
| |
| public String getExpressionSymbol() |
| { |
| return "-"; |
| } |
| } |
| |
| private static class InExpression<E extends Exception> extends BooleanUnaryExpression<E> |
| { |
| private final Collection _inList; |
| private final boolean _not; |
| |
| public InExpression(final PropertyExpression<E> right, final Collection inList, final boolean not) |
| { |
| super(right); |
| _inList = inList; |
| _not = not; |
| } |
| |
| public Object evaluate(Filterable<E> message) throws E |
| { |
| |
| Object rvalue = right.evaluate(message); |
| if (rvalue == null) |
| { |
| return null; |
| } |
| |
| if (rvalue.getClass() != String.class) |
| { |
| return null; |
| } |
| |
| if (((_inList != null) && _inList.contains(rvalue)) ^ _not) |
| { |
| return Boolean.TRUE; |
| } |
| else |
| { |
| return Boolean.FALSE; |
| } |
| |
| } |
| |
| public String toString() |
| { |
| StringBuffer answer = new StringBuffer(); |
| answer.append(right); |
| answer.append(" "); |
| answer.append(getExpressionSymbol()); |
| answer.append(" ( "); |
| |
| int count = 0; |
| for (Iterator i = _inList.iterator(); i.hasNext();) |
| { |
| Object o = (Object) i.next(); |
| if (count != 0) |
| { |
| answer.append(", "); |
| } |
| |
| answer.append(o); |
| count++; |
| } |
| |
| answer.append(" )"); |
| |
| return answer.toString(); |
| } |
| |
| public String getExpressionSymbol() |
| { |
| if (_not) |
| { |
| return "NOT IN"; |
| } |
| else |
| { |
| return "IN"; |
| } |
| } |
| } |
| |
| private static class NotExpression<E extends Exception> extends BooleanUnaryExpression<E> |
| { |
| public NotExpression(final BooleanExpression<E> left) |
| { |
| super(left); |
| } |
| |
| public Object evaluate(Filterable<E> message) throws E |
| { |
| Boolean lvalue = (Boolean) right.evaluate(message); |
| if (lvalue == null) |
| { |
| return null; |
| } |
| |
| return lvalue.booleanValue() ? Boolean.FALSE : Boolean.TRUE; |
| } |
| |
| public String getExpressionSymbol() |
| { |
| return "NOT"; |
| } |
| } |
| |
| private static class BooleanCastExpression<E extends Exception> extends BooleanUnaryExpression<E> |
| { |
| public BooleanCastExpression(final Expression<E> left) |
| { |
| super(left); |
| } |
| |
| public Object evaluate(Filterable<E> message) throws E |
| { |
| Object rvalue = right.evaluate(message); |
| if (rvalue == null) |
| { |
| return null; |
| } |
| |
| if (!rvalue.getClass().equals(Boolean.class)) |
| { |
| return Boolean.FALSE; |
| } |
| |
| return ((Boolean) rvalue).booleanValue() ? Boolean.TRUE : Boolean.FALSE; |
| } |
| |
| public String toString() |
| { |
| return right.toString(); |
| } |
| |
| public String getExpressionSymbol() |
| { |
| return ""; |
| } |
| } |
| } |