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    1   /*
    2    $Id: PropertyExpression.java,v 1.4 2004/07/10 03:31:37 bran Exp $
    3
    4    Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
    5
    6    Redistribution and use of this software and associated documentation
    7    ("Software"), with or without modification, are permitted provided
    8    that the following conditions are met:
    9
    10   1. Redistributions of source code must retain copyright
    11      statements and notices.  Redistributions must also contain a
    12      copy of this document.
    13
    14   2. Redistributions in binary form must reproduce the
    15      above copyright notice, this list of conditions and the
    16      following disclaimer in the documentation and/or other
    17      materials provided with the distribution.
    18
    19   3. The name "groovy" must not be used to endorse or promote
    20      products derived from this Software without prior written
    21      permission of The Codehaus.  For written permission,
    22      please contact info@codehaus.org.
    23
    24   4. Products derived from this Software may not be called "groovy"
    25      nor may "groovy" appear in their names without prior written
    26      permission of The Codehaus. "groovy" is a registered
    27      trademark of The Codehaus.
    28
    29   5. Due credit should be given to The Codehaus -
    30      http://groovy.codehaus.org/
    31
    32   THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
    33   ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
    34   NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
    35   FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
    36   THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
    37   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    38   (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    39   SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    40   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
    41   STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    42   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
    43   OF THE POSSIBILITY OF SUCH DAMAGE.
    44
    45   */
    46  package org.codehaus.groovy.ast.expr;
    47
    48  import java.lang.reflect.Field;
    49  import java.lang.reflect.Method;
    50  import java.lang.reflect.Modifier;
    51
    52  import org.codehaus.groovy.ast.GroovyCodeVisitor;
    53  import org.codehaus.groovy.classgen.AsmClassGenerator2;
    54
    55  /***
    56   * Represents a property access such as the expression "foo.bar".
    57   *
    58   * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
    59   * @version $Revision: 1.4 $
    60   */
    61  public class PropertyExpression extends Expression {
    62
    63      private Expression objectExpression;
    64      private String property;
    65      private boolean safe;
    66      private boolean isStatic = false;
    67
    68      private Method getter = null;
    69      private Method setter = null;
    70
    71      private Field field = null;
    72      private int access = -1;
    73
    74      public boolean isStatic() {
    75          return isStatic;
    76      }
    77
    78      public PropertyExpression(Expression objectExpression, String property) {
    79          this(objectExpression, property, false);
    80      }
    81
    82      public PropertyExpression(Expression objectExpression, String property, boolean safe) {
    83          this.objectExpression = objectExpression;
    84          this.property = property;
    85          this.safe = safe;
    86      }
    87
    88      public void visit(GroovyCodeVisitor visitor) {
    89          visitor.visitPropertyExpression(this);
    90      }
    91
    92      public boolean isDynamic() {
    93          return true;
    94      }
    95
    96      public Expression transformExpression(ExpressionTransformer transformer) {
    97          return this;
    98      }
    99
    100     protected void resolveType(AsmClassGenerator2 resolver) {
    101         objectExpression.resolve(resolver);
    102         resolver.resolve(this);
    103     }
    104
    105     public Expression getObjectExpression() {
    106         return objectExpression;
    107     }
    108
    109     public String getProperty() {
    110         return property;
    111     }
    112
    113     public String getText() {
    114         return objectExpression.getText() + "." + property;
    115     }
    116
    117     /***
    118      * @return is this a safe navigation, i.e. if true then if the source object is null
    119      * then this navigation will return null
    120      */
    121     public boolean isSafe() {
    122         return safe;
    123     }
    124
    125     public String toString() {
    126         return super.toString() + "[object: " + objectExpression + " property: " + property + "]";
    127     }
    128
    129     public void setStatic(boolean aStatic) {
    130         this.isStatic = aStatic;
    131     }
    132
    133     public void setGetter(Method meth) {
    134         Class returntype = meth.getReturnType();
    135         Class oldType = getTypeClass();
    136         if (oldType != null && oldType != Object.class && oldType != returntype) {
    137             // something is wrong
    138 // in this rare case the getter is discarded. Field access takes over
    139 //            String msg = "PropertyExpression.setSetter(): type mismatch: was " + getTypeClass() +
    140 //                    ". now " + returntype;
    141 //            System.err.println(msg);
    142 //            setResolveFailed(true);
    143 //            setFailure(msg);
    144         }
    145         else {
    146             getter = meth;
    147             setTypeClass(returntype);
    148             setTypeResolved(true);
    149         }
    150     }
    151
    152     public Method getGetter() {
    153         return getter;
    154     }
    155
    156     public void setSetter(Method method) {
    157         Class paramType = method.getParameterTypes()[0];
    158         Class wasType = getTypeClass();
    159         if (wasType != null && wasType != Object.class && wasType != paramType) {
    160 //            // something is wrong
    161 // in this rare case the getter is discarded. Field access takes over
    162 //            String msg = "PropertyExpression.setSetter(): type mismatch: was " + getTypeClass() +
    163 //                    ". now " + paramType;
    164 //            System.err.println(msg);
    165 //            setResolveFailed(true);
    166 //            setFailure(msg);
    167         }
    168         else {
    169             setter = method;
    170             setTypeClass(paramType);
    171             setTypeResolved(true);
    172         }
    173     }
    174     public Method getSetter() {
    175         return setter;
    176     }
    177
    178     public void setField(Field fld) {
    179         field = fld;
    180         setStatic(Modifier.isStatic(fld.getModifiers()));
    181         setTypeClass(fld.getType());
    182     }
    183     public Field getField() {
    184         return field;
    185     }
    186
    187     public void setAccess(int access) {
    188         this.access = access;
    189     }
    190
    191     public int getAccess() {
    192         return access;
    193     }
    194 }