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Diffstat (limited to 'libjava/classpath/java/beans/IndexedPropertyDescriptor.java')
| -rw-r--r-- | libjava/classpath/java/beans/IndexedPropertyDescriptor.java | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/libjava/classpath/java/beans/IndexedPropertyDescriptor.java b/libjava/classpath/java/beans/IndexedPropertyDescriptor.java new file mode 100644 index 00000000000..efdc7b40238 --- /dev/null +++ b/libjava/classpath/java/beans/IndexedPropertyDescriptor.java @@ -0,0 +1,307 @@ +/* java.beans.IndexedPropertyDescriptor + Copyright (C) 1998, 2003 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package java.beans; + +import java.lang.reflect.Array; +import java.lang.reflect.Method; + +/** + ** IndexedPropertyDescriptor describes information about a JavaBean + ** indexed property, by which we mean an array-like property that + ** has been exposed via a pair of get and set methods and another + ** pair that allows you to get to the property by an index.<P> + ** + ** An example property would have four methods like this:<P> + ** <CODE>FooBar[] getFoo()</CODE><BR> + ** <CODE>void setFoo(FooBar[])</CODE><BR> + ** <CODE>FooBar getFoo(int)</CODE><BR> + ** <CODE>void setFoo(int,FooBar)</CODE><P> + ** + ** The constraints put on get and set methods are:<P> + ** <OL> + ** <LI>There must be at least a get(int) or a set(int,...) method. + ** Nothing else is required. <B>Spec note:</B>One nice restriction + ** would be that if there is a get() there must be a get(int), same + ** with set, but that is not in the spec and is fairly harmless.)</LI> + ** <LI>A get array method must have signature + ** <CODE><propertyType>[] <getMethodName>()</CODE></LI> + ** <LI>A set array method must have signature + ** <CODE>void <setMethodName>(<propertyType>[])</CODE></LI> + ** <LI>A get index method must have signature + ** <CODE><propertyType> <getMethodName>(int)</CODE></LI> + ** <LI>A set index method must have signature + ** <CODE>void <setMethodName>(int,<propertyType>)</CODE></LI> + ** <LI>All these methods may throw any exception.</LI> + ** <LI>All these methods must be public.</LI> + ** </OL> + ** + ** @author John Keiser + ** @since JDK1.1 + ** @version 1.1.0, 26 Jul 1998 + **/ + +public class IndexedPropertyDescriptor extends PropertyDescriptor { + private Class indexedPropertyType; + private Method setIndex; + private Method getIndex; + + /** Create a new IndexedPropertyDescriptor by introspection. + ** This form of constructor creates the PropertyDescriptor by + ** looking for getter methods named <CODE>get<name>()</CODE> + ** and setter methods named + ** <CODE>set<name>()</CODE> in class + ** <CODE><beanClass></CODE>, where <name> has its + ** first letter capitalized by the constructor.<P> + ** + ** <B>Implementation note:</B> If there is a get(int) method, + ** then the return type of that method is used to find the + ** remaining methods. If there is no get method, then the + ** set(int) method is searched for exhaustively and that type + ** is used to find the others.<P> + ** + ** <B>Spec note:</B> + ** If there is no get(int) method and multiple set(int) methods with + ** the same name and the correct parameters (different type of course), + ** then an IntrospectionException is thrown. While Sun's spec + ** does not state this, it can make Bean behavior different on + ** different systems (since method order is not guaranteed) and as + ** such, can be treated as a bug in the spec. I am not aware of + ** whether Sun's implementation catches this. + ** + ** @param name the programmatic name of the property, usually + ** starting with a lowercase letter (e.g. fooManChu + ** instead of FooManChu). + ** @param beanClass the class the get and set methods live in. + ** @exception IntrospectionException if the methods are not found or invalid. + **/ + public IndexedPropertyDescriptor(String name, Class beanClass) throws IntrospectionException { + super(name); + String capitalized; + try { + capitalized = Character.toUpperCase(name.charAt(0)) + name.substring(1); + } catch(StringIndexOutOfBoundsException e) { + capitalized = ""; + } + findMethods(beanClass, "get" + capitalized, "set" + capitalized, "get" + capitalized, "set" + capitalized); + } + + /** Create a new IndexedPropertyDescriptor by introspection. + ** This form of constructor allows you to specify the + ** names of the get and set methods to search for.<P> + ** + ** <B>Implementation note:</B> If there is a get(int) method, + ** then the return type of that method is used to find the + ** remaining methods. If there is no get method, then the + ** set(int) method is searched for exhaustively and that type + ** is used to find the others.<P> + ** + ** <B>Spec note:</B> + ** If there is no get(int) method and multiple set(int) methods with + ** the same name and the correct parameters (different type of course), + ** then an IntrospectionException is thrown. While Sun's spec + ** does not state this, it can make Bean behavior different on + ** different systems (since method order is not guaranteed) and as + ** such, can be treated as a bug in the spec. I am not aware of + ** whether Sun's implementation catches this. + ** + ** @param name the programmatic name of the property, usually + ** starting with a lowercase letter (e.g. fooManChu + ** instead of FooManChu). + ** @param beanClass the class the get and set methods live in. + ** @param getMethodName the name of the get array method. + ** @param setMethodName the name of the set array method. + ** @param getIndexName the name of the get index method. + ** @param setIndexName the name of the set index method. + ** @exception IntrospectionException if the methods are not found or invalid. + **/ + public IndexedPropertyDescriptor(String name, Class beanClass, String getMethodName, String setMethodName, String getIndexName, String setIndexName) throws IntrospectionException { + super(name); + findMethods(beanClass, getMethodName, setMethodName, getIndexName, setIndexName); + } + + /** Create a new PropertyDescriptor using explicit Methods. + ** Note that the methods will be checked for conformance to standard + ** Property method rules, as described above at the top of this class. + ** + ** @param name the programmatic name of the property, usually + ** starting with a lowercase letter (e.g. fooManChu + ** instead of FooManChu). + ** @param getMethod the get array method. + ** @param setMethod the set array method. + ** @param getIndex the get index method. + ** @param setIndex the set index method. + ** @exception IntrospectionException if the methods are not found or invalid. + **/ + public IndexedPropertyDescriptor(String name, Method getMethod, Method setMethod, Method getIndex, Method setIndex) throws IntrospectionException { + super(name); + if(getMethod != null && getMethod.getParameterTypes().length > 0) { + throw new IntrospectionException("get method has parameters"); + } + if(getMethod != null && setMethod.getParameterTypes().length != 1) { + throw new IntrospectionException("set method does not have exactly one parameter"); + } + if(getMethod != null && setMethod != null) { + if(!getMethod.getReturnType().equals(setMethod.getParameterTypes()[0])) { + throw new IntrospectionException("set and get methods do not share the same type"); + } + if(!getMethod.getDeclaringClass().isAssignableFrom(setMethod.getDeclaringClass()) + && !setMethod.getDeclaringClass().isAssignableFrom(getMethod.getDeclaringClass())) { + throw new IntrospectionException("set and get methods are not in the same class."); + } + } + + if(getIndex != null && (getIndex.getParameterTypes().length != 1 + || !(getIndex.getParameterTypes()[0]).equals(java.lang.Integer.TYPE))) { + throw new IntrospectionException("get index method has wrong parameters"); + } + if(setIndex != null && (setIndex.getParameterTypes().length != 2 + || !(setIndex.getParameterTypes()[0]).equals(java.lang.Integer.TYPE))) { + throw new IntrospectionException("set index method has wrong parameters"); + } + if(getIndex != null && setIndex != null) { + if(!getIndex.getReturnType().equals(setIndex.getParameterTypes()[1])) { + throw new IntrospectionException("set index methods do not share the same type"); + } + if(!getIndex.getDeclaringClass().isAssignableFrom(setIndex.getDeclaringClass()) + && !setIndex.getDeclaringClass().isAssignableFrom(getIndex.getDeclaringClass())) { + throw new IntrospectionException("get and set index methods are not in the same class."); + } + } + + if(getIndex != null && getMethod != null && !getIndex.getDeclaringClass().isAssignableFrom(getMethod.getDeclaringClass()) + && !getMethod.getDeclaringClass().isAssignableFrom(getIndex.getDeclaringClass())) { + throw new IntrospectionException("methods are not in the same class."); + } + + if(getIndex != null && getMethod != null && !Array.newInstance(getIndex.getReturnType(),0).getClass().equals(getMethod.getReturnType())) { + throw new IntrospectionException("array methods do not match index methods."); + } + + this.getMethod = getMethod; + this.setMethod = setMethod; + this.getIndex = getIndex; + this.setIndex = setIndex; + this.indexedPropertyType = getIndex != null ? getIndex.getReturnType() : setIndex.getParameterTypes()[1]; + this.propertyType = getMethod != null ? getMethod.getReturnType() : (setMethod != null ? setMethod.getParameterTypes()[0] : Array.newInstance(this.indexedPropertyType,0).getClass()); + } + + public Class getIndexedPropertyType() { + return indexedPropertyType; + } + + public Method getIndexedReadMethod() { + return getIndex; + } + + public Method getIndexedWriteMethod() { + return setIndex; + } + + private void findMethods(Class beanClass, String getMethodName, String setMethodName, String getIndexName, String setIndexName) throws IntrospectionException { + try { + if(getIndexName != null) { + try { + Class[] getArgs = new Class[1]; + getArgs[0] = java.lang.Integer.TYPE; + getIndex = beanClass.getMethod(getIndexName,getArgs); + indexedPropertyType = getIndex.getReturnType(); + } catch(NoSuchMethodException E) { + } + } + if(getIndex != null) { + if(setIndexName != null) { + try { + Class[] setArgs = new Class[2]; + setArgs[0] = java.lang.Integer.TYPE; + setArgs[1] = indexedPropertyType; + setIndex = beanClass.getMethod(setIndexName,setArgs); + if(!setIndex.getReturnType().equals(java.lang.Void.TYPE)) { + throw new IntrospectionException(setIndexName + " has non-void return type"); + } + } catch(NoSuchMethodException E) { + } + } + } else if(setIndexName != null) { + Method[] m = beanClass.getMethods(); + for(int i=0;i<m.length;i++) { + Method current = m[i]; + if(current.getName().equals(setIndexName) + && current.getParameterTypes().length == 2 + && (current.getParameterTypes()[0]).equals(java.lang.Integer.TYPE) + && current.getReturnType().equals(java.lang.Void.TYPE)) { + if(setIndex != null) { + throw new IntrospectionException("Multiple, different set methods found that fit the bill!"); + } else { + setIndex = current; + indexedPropertyType = current.getParameterTypes()[1]; + } + } + } + if(setIndex == null) { + throw new IntrospectionException("Cannot find get or set methods."); + } + } else { + throw new IntrospectionException("Cannot find get or set methods."); + } + + Class arrayType = Array.newInstance(indexedPropertyType,0).getClass(); + + Class[] setArgs = new Class[1]; + setArgs[0] = arrayType; + try { + setMethod = beanClass.getMethod(setMethodName,setArgs); + if(!setMethod.getReturnType().equals(java.lang.Void.TYPE)) { + setMethod = null; + } + } catch(NoSuchMethodException E) { + } + + Class[] getArgs = new Class[0]; + try { + getMethod = beanClass.getMethod(getMethodName,getArgs); + if(!getMethod.getReturnType().equals(arrayType)) { + getMethod = null; + } + } catch(NoSuchMethodException E) { + } + } catch(SecurityException E) { + throw new IntrospectionException("SecurityException while trying to find methods."); + } + } +} |
