|
1
61
62
63
64 package org.jaxen.expr;
65
66 import java.util.Iterator  ;
67 import java.util.List ;
68 import org.jaxen.Context;
69 import org.jaxen.JaxenException;
70 import org.jaxen.Navigator;
71 import org.jaxen.function.NumberFunction;
72
73 abstract class DefaultRelationalExpr extends DefaultTruthExpr implements RelationalExpr
74 {
75 DefaultRelationalExpr( Expr lhs, Expr rhs )
76 {
77 super( lhs, rhs );
78 }
79
80 public String toString()
81 {
82 return "[(DefaultRelationalExpr): " + getLHS() + ", " + getRHS() + "]";
83 }
84
85 public Object evaluate( Context context ) throws JaxenException
86 {
87 Object lhsValue = getLHS().evaluate( context );
88 Object rhsValue = getRHS().evaluate( context );
89 Navigator nav = context.getNavigator();
90
91 if( bothAreSets( lhsValue, rhsValue ) )
92 {
93 return evaluateSetSet( (List ) lhsValue, (List ) rhsValue, nav );
94 }
95
96 if( eitherIsSet( lhsValue, rhsValue ) )
97 {
98 if( isSet( lhsValue ) )
99 {
100 return evaluateSetSet( (List ) lhsValue, convertToList( rhsValue ), nav );
101 }
102 else
103 {
104 return evaluateSetSet( convertToList( lhsValue ), (List ) rhsValue, nav );
105 }
106 }
107
108 return evaluateObjectObject( lhsValue, rhsValue, nav ) ? Boolean.TRUE : Boolean.FALSE;
109 }
110
111 private Object evaluateSetSet( List lhsSet, List rhsSet, Navigator nav )
112 {
113 if( setIsEmpty( lhsSet ) || setIsEmpty( rhsSet ) ) {
115 return Boolean.FALSE;
116 }
117
118 for( Iterator lhsIterator = lhsSet.iterator(); lhsIterator.hasNext(); )
119 {
120 Object lhs = lhsIterator.next();
121
122 for( Iterator rhsIterator = rhsSet.iterator(); rhsIterator.hasNext(); )
123 {
124 Object rhs = rhsIterator.next();
125
126 if( evaluateObjectObject( lhs, rhs, nav ) )
127 {
128 return Boolean.TRUE;
129 }
130 }
131 }
132
133 return Boolean.FALSE;
134 }
135
136 private boolean evaluateObjectObject( Object lhs, Object rhs, Navigator nav )
137 {
138 if( lhs == null || rhs == null )
139 {
140 return false;
141 }
142
143 Double lhsNum = NumberFunction.evaluate( lhs, nav );
144 Double rhsNum = NumberFunction.evaluate( rhs, nav );
145
146 if( NumberFunction.isNaN( lhsNum ) || NumberFunction.isNaN( rhsNum ) )
147 {
148 return false;
149 }
150
151 return evaluateDoubleDouble( lhsNum, rhsNum );
152 }
153
154 protected abstract boolean evaluateDoubleDouble( Double lhs, Double rhs );
155 }
156
157 |
Popular Tags |
Java API By Example, From Geeks To Geeks.