/interpreter/tags/at2dist130208/src/edu/vub/at/objects/symbiosis/JavaField.java
Java | 103 lines | 54 code | 13 blank | 36 comment | 5 complexity | 8d5d30546429f557f54252ffcb9edc5f MD5 | raw file
1/** 2 * AmbientTalk/2 Project 3 * JavaField.java created on 5-nov-2006 at 20:08:18 4 * (c) Programming Technology Lab, 2006 - 2007 5 * Authors: Tom Van Cutsem & Stijn Mostinckx 6 * 7 * Permission is hereby granted, free of charge, to any person 8 * obtaining a copy of this software and associated documentation 9 * files (the "Software"), to deal in the Software without 10 * restriction, including without limitation the rights to use, 11 * copy, modify, merge, publish, distribute, sublicense, and/or 12 * sell copies of the Software, and to permit persons to whom the 13 * Software is furnished to do so, subject to the following 14 * conditions: 15 * 16 * The above copyright notice and this permission notice shall be 17 * included in all copies or substantial portions of the Software. 18 * 19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 20 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES 21 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 22 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 23 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 24 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 25 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 26 * OTHER DEALINGS IN THE SOFTWARE. 27 */ 28package edu.vub.at.objects.symbiosis; 29 30import edu.vub.at.exceptions.InterpreterException; 31import edu.vub.at.exceptions.XIllegalArgument; 32import edu.vub.at.objects.ATField; 33import edu.vub.at.objects.ATObject; 34import edu.vub.at.objects.ATTable; 35import edu.vub.at.objects.coercion.NativeTypeTags; 36import edu.vub.at.objects.grammar.ATSymbol; 37import edu.vub.at.objects.mirrors.Reflection; 38import edu.vub.at.objects.natives.NATByRef; 39import edu.vub.at.objects.natives.OBJNil; 40import edu.vub.at.objects.natives.NATNumber; 41import edu.vub.at.objects.natives.NATTable; 42import edu.vub.at.objects.natives.NATText; 43 44import java.lang.reflect.Field; 45 46/** 47 * A JavaField is a simple wrapper around a native java.lang.reflect.Field 48 * 49 * @author tvcutsem 50 */ 51public final class JavaField extends NATByRef implements ATField { 52 53 private final Object host_; 54 private final Field field_; 55 56 public JavaField(Object host, Field f) { 57 host_ = host; 58 field_ = f; 59 } 60 61 public ATSymbol base_name() { 62 return Reflection.downSelector(field_.getName()); 63 } 64 65 public ATObject base_readField() throws InterpreterException { 66 return Symbiosis.readField(host_, field_); 67 } 68 69 public ATObject base_writeField(ATObject newValue) throws InterpreterException { 70 Symbiosis.writeField(host_, field_, newValue); 71 return OBJNil._INSTANCE_; 72 } 73 74 public NATText meta_print() throws InterpreterException { 75 return NATText.atValue("<java field:"+field_+">"); 76 } 77 78 public ATField asField() { 79 return this; 80 } 81 82 /** 83 * Fields can be re-initialized when installed in an object that is being cloned. 84 * They expect the new owner of the field as the sole instance to their 'new' method 85 */ 86 public ATObject meta_newInstance(ATTable initargs) throws InterpreterException { 87 if (initargs.base_length() != NATNumber.ONE) { 88 return super.meta_newInstance(initargs); 89 } else { 90 ATObject newhost = initargs.base_at(NATNumber.ONE); 91 if (newhost.isJavaObjectUnderSymbiosis()) { 92 return new JavaField(newhost.asJavaObjectUnderSymbiosis().getWrappedObject(), field_); 93 } else { 94 throw new XIllegalArgument("Java Field re-initialization requires a symbiotic Java object, given " + newhost); 95 } 96 } 97 } 98 99 public ATTable meta_typeTags() throws InterpreterException { 100 return NATTable.of(NativeTypeTags._FIELD_); 101 } 102 103}