Java tutorial
/* * Copyright (c) 1996, 2019, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.beans; import java.awt.Component; import java.lang.ref.Reference; import java.lang.ref.SoftReference; import java.lang.reflect.Constructor; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.lang.reflect.Type; import java.util.ArrayList; import java.util.EventObject; import java.util.HashMap; import java.util.Iterator; import java.util.List; import java.util.Map; import java.util.TreeMap; import com.sun.beans.TypeResolver; import com.sun.beans.finder.ClassFinder; import com.sun.beans.introspect.ClassInfo; import com.sun.beans.introspect.EventSetInfo; import com.sun.beans.introspect.PropertyInfo; import jdk.internal.access.JavaBeansAccess; import jdk.internal.access.SharedSecrets; import sun.reflect.misc.ReflectUtil; /** * The Introspector class provides a standard way for tools to learn about * the properties, events, and methods supported by a target Java Bean. * <p> * For each of those three kinds of information, the Introspector will * separately analyze the bean's class and superclasses looking for * either explicit or implicit information and use that information to * build a BeanInfo object that comprehensively describes the target bean. * <p> * For each class "Foo", explicit information may be available if there exists * a corresponding "FooBeanInfo" class that provides a non-null value when * queried for the information. We first look for the BeanInfo class by * taking the full package-qualified name of the target bean class and * appending "BeanInfo" to form a new class name. If this fails, then * we take the final classname component of this name, and look for that * class in each of the packages specified in the BeanInfo package search * path. * <p> * Thus for a class such as "sun.xyz.OurButton" we would first look for a * BeanInfo class called "sun.xyz.OurButtonBeanInfo" and if that failed we'd * look in each package in the BeanInfo search path for an OurButtonBeanInfo * class. With the default search path, this would mean looking for * "sun.beans.infos.OurButtonBeanInfo". * <p> * If a class provides explicit BeanInfo about itself then we add that to * the BeanInfo information we obtained from analyzing any derived classes, * but we regard the explicit information as being definitive for the current * class and its base classes, and do not proceed any further up the superclass * chain. * <p> * If we don't find explicit BeanInfo on a class, we use low-level * reflection to study the methods of the class and apply standard design * patterns to identify property accessors, event sources, or public * methods. We then proceed to analyze the class's superclass and add * in the information from it (and possibly on up the superclass chain). * <p> * For more information about introspection and design patterns, please * consult the * <a href="http://www.oracle.com/technetwork/java/javase/documentation/spec-136004.html">JavaBeans™ specification</a>. * * @since 1.1 */ public class Introspector { // Flags that can be used to control getBeanInfo: /** * Flag to indicate to use of all beaninfo. * @since 1.2 */ public static final int USE_ALL_BEANINFO = 1; /** * Flag to indicate to ignore immediate beaninfo. * @since 1.2 */ public static final int IGNORE_IMMEDIATE_BEANINFO = 2; /** * Flag to indicate to ignore all beaninfo. * @since 1.2 */ public static final int IGNORE_ALL_BEANINFO = 3; private Class<?> beanClass; private BeanInfo explicitBeanInfo; private BeanInfo superBeanInfo; private BeanInfo[] additionalBeanInfo; private boolean propertyChangeSource = false; // These should be removed. private String defaultEventName; private String defaultPropertyName; private int defaultEventIndex = -1; private int defaultPropertyIndex = -1; // Methods maps from Method names to MethodDescriptors private Map<String, MethodDescriptor> methods; // properties maps from String names to PropertyDescriptors private Map<String, PropertyDescriptor> properties; // events maps from String names to EventSetDescriptors private Map<String, EventSetDescriptor> events; private static final EventSetDescriptor[] EMPTY_EVENTSETDESCRIPTORS = new EventSetDescriptor[0]; static final String ADD_PREFIX = "add"; static final String REMOVE_PREFIX = "remove"; static final String GET_PREFIX = "get"; static final String SET_PREFIX = "set"; static final String IS_PREFIX = "is"; // register with SharedSecrets for JMX usage static { SharedSecrets.setJavaBeansAccess(new JavaBeansAccess() { @Override public Method getReadMethod(Class<?> clazz, String property) throws Exception { BeanInfo bi = Introspector.getBeanInfo(clazz); PropertyDescriptor[] pds = bi.getPropertyDescriptors(); for (PropertyDescriptor pd : pds) { if (pd.getName().equals(property)) { return pd.getReadMethod(); } } return null; } @Override public String[] getConstructorPropertiesValue(Constructor<?> ctr) { ConstructorProperties cp = ctr.getAnnotation(ConstructorProperties.class); String[] ret = cp != null ? cp.value() : null; return ret; } }); } //====================================================================== // Public methods //====================================================================== /** * Introspect on a Java Bean and learn about all its properties, exposed * methods, and events. * <p> * If the BeanInfo class for a Java Bean has been previously Introspected * then the BeanInfo class is retrieved from the BeanInfo cache. * * @param beanClass The bean class to be analyzed. * @return A BeanInfo object describing the target bean. * @exception IntrospectionException if an exception occurs during * introspection. * @see #flushCaches * @see #flushFromCaches */ public static BeanInfo getBeanInfo(Class<?> beanClass) throws IntrospectionException { if (!ReflectUtil.isPackageAccessible(beanClass)) { return (new Introspector(beanClass, null, USE_ALL_BEANINFO)).getBeanInfo(); } ThreadGroupContext context = ThreadGroupContext.getContext(); BeanInfo beanInfo = context.getBeanInfo(beanClass); if (beanInfo == null) { beanInfo = new Introspector(beanClass, null, USE_ALL_BEANINFO).getBeanInfo(); context.putBeanInfo(beanClass, beanInfo); } return beanInfo; } /** * Introspect on a Java bean and learn about all its properties, exposed * methods, and events, subject to some control flags. * <p> * If the BeanInfo class for a Java Bean has been previously Introspected * based on the same arguments then the BeanInfo class is retrieved * from the BeanInfo cache. * * @param beanClass The bean class to be analyzed. * @param flags Flags to control the introspection. * If flags == USE_ALL_BEANINFO then we use all of the BeanInfo * classes we can discover. * If flags == IGNORE_IMMEDIATE_BEANINFO then we ignore any * BeanInfo associated with the specified beanClass. * If flags == IGNORE_ALL_BEANINFO then we ignore all BeanInfo * associated with the specified beanClass or any of its * parent classes. * @return A BeanInfo object describing the target bean. * @exception IntrospectionException if an exception occurs during * introspection. * @since 1.2 */ public static BeanInfo getBeanInfo(Class<?> beanClass, int flags) throws IntrospectionException { return getBeanInfo(beanClass, null, flags); } /** * Introspect on a Java bean and learn all about its properties, exposed * methods, below a given "stop" point. * <p> * If the BeanInfo class for a Java Bean has been previously Introspected * based on the same arguments, then the BeanInfo class is retrieved * from the BeanInfo cache. * @return the BeanInfo for the bean * @param beanClass The bean class to be analyzed. * @param stopClass The baseclass at which to stop the analysis. Any * methods/properties/events in the stopClass or in its baseclasses * will be ignored in the analysis. * @exception IntrospectionException if an exception occurs during * introspection. */ public static BeanInfo getBeanInfo(Class<?> beanClass, Class<?> stopClass) throws IntrospectionException { return getBeanInfo(beanClass, stopClass, USE_ALL_BEANINFO); } /** * Introspect on a Java Bean and learn about all its properties, * exposed methods and events, below a given {@code stopClass} point * subject to some control {@code flags}. * <dl> * <dt>USE_ALL_BEANINFO</dt> * <dd>Any BeanInfo that can be discovered will be used.</dd> * <dt>IGNORE_IMMEDIATE_BEANINFO</dt> * <dd>Any BeanInfo associated with the specified {@code beanClass} will be ignored.</dd> * <dt>IGNORE_ALL_BEANINFO</dt> * <dd>Any BeanInfo associated with the specified {@code beanClass} * or any of its parent classes will be ignored.</dd> * </dl> * Any methods/properties/events in the {@code stopClass} * or in its parent classes will be ignored in the analysis. * <p> * If the BeanInfo class for a Java Bean has been * previously introspected based on the same arguments then * the BeanInfo class is retrieved from the BeanInfo cache. * * @param beanClass the bean class to be analyzed * @param stopClass the parent class at which to stop the analysis * @param flags flags to control the introspection * @return a BeanInfo object describing the target bean * @exception IntrospectionException if an exception occurs during introspection * * @since 1.7 */ public static BeanInfo getBeanInfo(Class<?> beanClass, Class<?> stopClass, int flags) throws IntrospectionException { BeanInfo bi; if (stopClass == null && flags == USE_ALL_BEANINFO) { // Same parameters to take advantage of caching. bi = getBeanInfo(beanClass); } else { bi = (new Introspector(beanClass, stopClass, flags)).getBeanInfo(); } return bi; // Old behaviour: Make an independent copy of the BeanInfo. //return new GenericBeanInfo(bi); } /** * Utility method to take a string and convert it to normal Java variable * name capitalization. This normally means converting the first * character from upper case to lower case, but in the (unusual) special * case when there is more than one character and both the first and * second characters are upper case, we leave it alone. * <p> * Thus "FooBah" becomes "fooBah" and "X" becomes "x", but "URL" stays * as "URL". * * @param name The string to be decapitalized. * @return The decapitalized version of the string. */ public static String decapitalize(String name) { if (name == null || name.length() == 0) { return name; } if (name.length() > 1 && Character.isUpperCase(name.charAt(1)) && Character.isUpperCase(name.charAt(0))) { return name; } char[] chars = name.toCharArray(); chars[0] = Character.toLowerCase(chars[0]); return new String(chars); } /** * Gets the list of package names that will be used for * finding BeanInfo classes. * * @return The array of package names that will be searched in * order to find BeanInfo classes. The default value * for this array is implementation-dependent; e.g. * Sun implementation initially sets to {"sun.beans.infos"}. */ public static String[] getBeanInfoSearchPath() { return ThreadGroupContext.getContext().getBeanInfoFinder().getPackages(); } /** * Change the list of package names that will be used for * finding BeanInfo classes. The behaviour of * this method is undefined if parameter path * is null. * * <p>First, if there is a security manager, its {@code checkPropertiesAccess} * method is called. This could result in a SecurityException. * * @param path Array of package names. * @exception SecurityException if a security manager exists and its * {@code checkPropertiesAccess} method doesn't allow setting * of system properties. * @see SecurityManager#checkPropertiesAccess */ public static void setBeanInfoSearchPath(String[] path) { SecurityManager sm = System.getSecurityManager(); if (sm != null) { sm.checkPropertiesAccess(); } ThreadGroupContext.getContext().getBeanInfoFinder().setPackages(path); } /** * Flush all of the Introspector's internal caches. This method is * not normally required. It is normally only needed by advanced * tools that update existing "Class" objects in-place and need * to make the Introspector re-analyze existing Class objects. * * @since 1.2 */ public static void flushCaches() { ThreadGroupContext.getContext().clearBeanInfoCache(); } /** * Flush the Introspector's internal cached information for a given class. * This method is not normally required. It is normally only needed * by advanced tools that update existing "Class" objects in-place * and need to make the Introspector re-analyze an existing Class object. * * Note that only the direct state associated with the target Class * object is flushed. We do not flush state for other Class objects * with the same name, nor do we flush state for any related Class * objects (such as subclasses), even though their state may include * information indirectly obtained from the target Class object. * * @param clz Class object to be flushed. * @throws NullPointerException If the Class object is null. * @since 1.2 */ public static void flushFromCaches(Class<?> clz) { if (clz == null) { throw new NullPointerException(); } ThreadGroupContext.getContext().removeBeanInfo(clz); } //====================================================================== // Private implementation methods //====================================================================== private Introspector(Class<?> beanClass, Class<?> stopClass, int flags) throws IntrospectionException { this.beanClass = beanClass; // Check stopClass is a superClass of startClass. if (stopClass != null) { boolean isSuper = false; for (Class<?> c = beanClass.getSuperclass(); c != null; c = c.getSuperclass()) { if (c == stopClass) { isSuper = true; } } if (!isSuper) { throw new IntrospectionException(stopClass.getName() + " not superclass of " + beanClass.getName()); } } if (flags == USE_ALL_BEANINFO) { explicitBeanInfo = findExplicitBeanInfo(beanClass); } Class<?> superClass = beanClass.getSuperclass(); if (superClass != stopClass) { int newFlags = flags; if (newFlags == IGNORE_IMMEDIATE_BEANINFO) { newFlags = USE_ALL_BEANINFO; } superBeanInfo = getBeanInfo(superClass, stopClass, newFlags); } if (explicitBeanInfo != null) { additionalBeanInfo = explicitBeanInfo.getAdditionalBeanInfo(); } if (additionalBeanInfo == null) { additionalBeanInfo = new BeanInfo[0]; } } /** * Constructs a GenericBeanInfo class from the state of the Introspector */ private BeanInfo getBeanInfo() throws IntrospectionException { // the evaluation order here is import, as we evaluate the // event sets and locate PropertyChangeListeners before we // look for properties. BeanDescriptor bd = getTargetBeanDescriptor(); MethodDescriptor[] mds = getTargetMethodInfo(); EventSetDescriptor[] esds = getTargetEventInfo(); PropertyDescriptor[] pds = getTargetPropertyInfo(); int defaultEvent = getTargetDefaultEventIndex(); int defaultProperty = getTargetDefaultPropertyIndex(); return new GenericBeanInfo(bd, esds, defaultEvent, pds, defaultProperty, mds, explicitBeanInfo); } /** * Looks for an explicit BeanInfo class that corresponds to the Class. * First it looks in the existing package that the Class is defined in, * then it checks to see if the class is its own BeanInfo. Finally, * the BeanInfo search path is prepended to the class and searched. * * @param beanClass the class type of the bean * @return Instance of an explicit BeanInfo class or null if one isn't found. */ private static BeanInfo findExplicitBeanInfo(Class<?> beanClass) { return ThreadGroupContext.getContext().getBeanInfoFinder().find(beanClass); } /** * @return An array of PropertyDescriptors describing the editable * properties supported by the target bean. */ private PropertyDescriptor[] getTargetPropertyInfo() { // Check if the bean has its own BeanInfo that will provide // explicit information. PropertyDescriptor[] explicitProperties = null; if (explicitBeanInfo != null) { explicitProperties = getPropertyDescriptors(this.explicitBeanInfo); } if (explicitProperties == null && superBeanInfo != null) { // We have no explicit BeanInfo properties. Check with our parent. addPropertyDescriptors(getPropertyDescriptors(this.superBeanInfo)); } for (int i = 0; i < additionalBeanInfo.length; i++) { addPropertyDescriptors(additionalBeanInfo[i].getPropertyDescriptors()); } if (explicitProperties != null) { // Add the explicit BeanInfo data to our results. addPropertyDescriptors(explicitProperties); } else { // Apply some reflection to the current class. for (Map.Entry<String, PropertyInfo> entry : ClassInfo.get(this.beanClass).getProperties().entrySet()) { addPropertyDescriptor(null != entry.getValue().getIndexed() ? new IndexedPropertyDescriptor(entry, this.propertyChangeSource) : new PropertyDescriptor(entry, this.propertyChangeSource)); } JavaBean annotation = this.beanClass.getAnnotation(JavaBean.class); if ((annotation != null) && !annotation.defaultProperty().isEmpty()) { this.defaultPropertyName = annotation.defaultProperty(); } } processPropertyDescriptors(); // Allocate and populate the result array. PropertyDescriptor[] result = properties.values().toArray(new PropertyDescriptor[properties.size()]); // Set the default index. if (defaultPropertyName != null) { for (int i = 0; i < result.length; i++) { if (defaultPropertyName.equals(result[i].getName())) { defaultPropertyIndex = i; } } } return result; } private HashMap<String, List<PropertyDescriptor>> pdStore = new HashMap<>(); /** * Adds the property descriptor to the list store. */ private void addPropertyDescriptor(PropertyDescriptor pd) { String propName = pd.getName(); List<PropertyDescriptor> list = pdStore.get(propName); if (list == null) { list = new ArrayList<>(); pdStore.put(propName, list); } if (this.beanClass != pd.getClass0()) { // replace existing property descriptor // only if we have types to resolve // in the context of this.beanClass Method read = pd.getReadMethod(); Method write = pd.getWriteMethod(); boolean cls = true; if (read != null) cls = cls && read.getGenericReturnType() instanceof Class; if (write != null) cls = cls && write.getGenericParameterTypes()[0] instanceof Class; if (pd instanceof IndexedPropertyDescriptor) { IndexedPropertyDescriptor ipd = (IndexedPropertyDescriptor) pd; Method readI = ipd.getIndexedReadMethod(); Method writeI = ipd.getIndexedWriteMethod(); if (readI != null) cls = cls && readI.getGenericReturnType() instanceof Class; if (writeI != null) cls = cls && writeI.getGenericParameterTypes()[1] instanceof Class; if (!cls) { pd = new IndexedPropertyDescriptor(ipd); pd.updateGenericsFor(this.beanClass); } } else if (!cls) { pd = new PropertyDescriptor(pd); pd.updateGenericsFor(this.beanClass); } } list.add(pd); } private void addPropertyDescriptors(PropertyDescriptor[] descriptors) { if (descriptors != null) { for (PropertyDescriptor descriptor : descriptors) { addPropertyDescriptor(descriptor); } } } private PropertyDescriptor[] getPropertyDescriptors(BeanInfo info) { PropertyDescriptor[] descriptors = info.getPropertyDescriptors(); int index = info.getDefaultPropertyIndex(); if ((0 <= index) && (index < descriptors.length)) { this.defaultPropertyName = descriptors[index].getName(); } return descriptors; } /** * Populates the property descriptor table by merging the * lists of Property descriptors. */ private void processPropertyDescriptors() { if (properties == null) { properties = new TreeMap<>(); } List<PropertyDescriptor> list; PropertyDescriptor pd, gpd, spd; IndexedPropertyDescriptor ipd, igpd, ispd; Iterator<List<PropertyDescriptor>> it = pdStore.values().iterator(); while (it.hasNext()) { pd = null; gpd = null; spd = null; ipd = null; igpd = null; ispd = null; list = it.next(); // First pass. Find the latest getter method. Merge properties // of previous getter methods. for (int i = 0; i < list.size(); i++) { pd = list.get(i); if (pd instanceof IndexedPropertyDescriptor) { ipd = (IndexedPropertyDescriptor) pd; if (ipd.getIndexedReadMethod() != null) { if (igpd != null) { igpd = new IndexedPropertyDescriptor(igpd, ipd); } else { igpd = ipd; } } } else { if (pd.getReadMethod() != null) { String pdName = pd.getReadMethod().getName(); if (gpd != null) { // Don't replace the existing read // method if it starts with "is" String gpdName = gpd.getReadMethod().getName(); if (gpdName.equals(pdName) || !gpdName.startsWith(IS_PREFIX)) { gpd = new PropertyDescriptor(gpd, pd); } } else { gpd = pd; } } } } // Second pass. Find the latest setter method which // has the same type as the getter method. for (int i = 0; i < list.size(); i++) { pd = list.get(i); if (pd instanceof IndexedPropertyDescriptor) { ipd = (IndexedPropertyDescriptor) pd; if (ipd.getIndexedWriteMethod() != null) { if (igpd != null) { if (isAssignable(igpd.getIndexedPropertyType(), ipd.getIndexedPropertyType())) { if (ispd != null) { ispd = new IndexedPropertyDescriptor(ispd, ipd); } else { ispd = ipd; } } } else { if (ispd != null) { ispd = new IndexedPropertyDescriptor(ispd, ipd); } else { ispd = ipd; } } } } else { if (pd.getWriteMethod() != null) { if (gpd != null) { if (isAssignable(gpd.getPropertyType(), pd.getPropertyType())) { if (spd != null) { spd = new PropertyDescriptor(spd, pd); } else { spd = pd; } } } else { if (spd != null) { spd = new PropertyDescriptor(spd, pd); } else { spd = pd; } } } } } // At this stage we should have either PDs or IPDs for the // representative getters and setters. The order at which the // property descriptors are determined represent the // precedence of the property ordering. pd = null; ipd = null; if (igpd != null && ispd != null) { // Complete indexed properties set // Merge any classic property descriptors if ((gpd == spd) || (gpd == null)) { pd = spd; } else if (spd == null) { pd = gpd; } else if (spd instanceof IndexedPropertyDescriptor) { pd = mergePropertyWithIndexedProperty(gpd, (IndexedPropertyDescriptor) spd); } else if (gpd instanceof IndexedPropertyDescriptor) { pd = mergePropertyWithIndexedProperty(spd, (IndexedPropertyDescriptor) gpd); } else { pd = mergePropertyDescriptor(gpd, spd); } if (igpd == ispd) { ipd = igpd; } else { ipd = mergePropertyDescriptor(igpd, ispd); } if (pd == null) { pd = ipd; } else { Class<?> propType = pd.getPropertyType(); Class<?> ipropType = ipd.getIndexedPropertyType(); if (propType.isArray() && propType.getComponentType() == ipropType) { pd = pd.getClass0().isAssignableFrom(ipd.getClass0()) ? new IndexedPropertyDescriptor(pd, ipd) : new IndexedPropertyDescriptor(ipd, pd); } else if (pd.getClass0().isAssignableFrom(ipd.getClass0())) { pd = pd.getClass0().isAssignableFrom(ipd.getClass0()) ? new PropertyDescriptor(pd, ipd) : new PropertyDescriptor(ipd, pd); } else { pd = ipd; } } } else if (gpd != null && spd != null) { if (igpd != null) { gpd = mergePropertyWithIndexedProperty(gpd, igpd); } if (ispd != null) { spd = mergePropertyWithIndexedProperty(spd, ispd); } // Complete simple properties set if (gpd == spd) { pd = gpd; } else if (spd instanceof IndexedPropertyDescriptor) { pd = mergePropertyWithIndexedProperty(gpd, (IndexedPropertyDescriptor) spd); } else if (gpd instanceof IndexedPropertyDescriptor) { pd = mergePropertyWithIndexedProperty(spd, (IndexedPropertyDescriptor) gpd); } else { pd = mergePropertyDescriptor(gpd, spd); } } else if (ispd != null) { // indexed setter pd = ispd; // Merge any classic property descriptors if (spd != null) { pd = mergePropertyDescriptor(ispd, spd); } if (gpd != null) { pd = mergePropertyDescriptor(ispd, gpd); } } else if (igpd != null) { // indexed getter pd = igpd; // Merge any classic property descriptors if (gpd != null) { pd = mergePropertyDescriptor(igpd, gpd); } if (spd != null) { pd = mergePropertyDescriptor(igpd, spd); } } else if (spd != null) { // simple setter pd = spd; } else if (gpd != null) { // simple getter pd = gpd; } // Very special case to ensure that an IndexedPropertyDescriptor // doesn't contain less information than the enclosed // PropertyDescriptor. If it does, then recreate as a // PropertyDescriptor. See 4168833 if (pd instanceof IndexedPropertyDescriptor) { ipd = (IndexedPropertyDescriptor) pd; if (ipd.getIndexedReadMethod() == null && ipd.getIndexedWriteMethod() == null) { pd = new PropertyDescriptor(ipd); } } // Find the first property descriptor // which does not have getter and setter methods. // See regression bug 4984912. if ((pd == null) && (list.size() > 0)) { pd = list.get(0); } if (pd != null) { properties.put(pd.getName(), pd); } } } private static boolean isAssignable(Class<?> current, Class<?> candidate) { return ((current == null) || (candidate == null)) ? current == candidate : current.isAssignableFrom(candidate); } private PropertyDescriptor mergePropertyWithIndexedProperty(PropertyDescriptor pd, IndexedPropertyDescriptor ipd) { Class<?> type = pd.getPropertyType(); if (type.isArray() && (type.getComponentType() == ipd.getIndexedPropertyType())) { return pd.getClass0().isAssignableFrom(ipd.getClass0()) ? new IndexedPropertyDescriptor(pd, ipd) : new IndexedPropertyDescriptor(ipd, pd); } return pd; } /** * Adds the property descriptor to the indexedproperty descriptor only if the * types are the same. * * The most specific property descriptor will take precedence. */ private PropertyDescriptor mergePropertyDescriptor(IndexedPropertyDescriptor ipd, PropertyDescriptor pd) { PropertyDescriptor result = null; Class<?> propType = pd.getPropertyType(); Class<?> ipropType = ipd.getIndexedPropertyType(); if (propType.isArray() && propType.getComponentType() == ipropType) { if (pd.getClass0().isAssignableFrom(ipd.getClass0())) { result = new IndexedPropertyDescriptor(pd, ipd); } else { result = new IndexedPropertyDescriptor(ipd, pd); } } else if ((ipd.getReadMethod() == null) && (ipd.getWriteMethod() == null)) { if (pd.getClass0().isAssignableFrom(ipd.getClass0())) { result = new PropertyDescriptor(pd, ipd); } else { result = new PropertyDescriptor(ipd, pd); } } else { // Cannot merge the pd because of type mismatch // Return the most specific pd if (pd.getClass0().isAssignableFrom(ipd.getClass0())) { result = ipd; } else { result = pd; // Try to add methods which may have been lost in the type change // See 4168833 Method write = result.getWriteMethod(); Method read = result.getReadMethod(); if (read == null && write != null) { read = findMethod(result.getClass0(), GET_PREFIX + NameGenerator.capitalize(result.getName()), 0); if (read != null) { try { result.setReadMethod(read); } catch (IntrospectionException ex) { // no consequences for failure. } } } if (write == null && read != null) { write = findMethod(result.getClass0(), SET_PREFIX + NameGenerator.capitalize(result.getName()), 1, new Class<?>[] { FeatureDescriptor.getReturnType(result.getClass0(), read) }); if (write != null) { try { result.setWriteMethod(write); } catch (IntrospectionException ex) { // no consequences for failure. } } } } } return result; } // Handle regular pd merge private PropertyDescriptor mergePropertyDescriptor(PropertyDescriptor pd1, PropertyDescriptor pd2) { if (pd1.getClass0().isAssignableFrom(pd2.getClass0())) { return new PropertyDescriptor(pd1, pd2); } else { return new PropertyDescriptor(pd2, pd1); } } // Handle regular ipd merge private IndexedPropertyDescriptor mergePropertyDescriptor(IndexedPropertyDescriptor ipd1, IndexedPropertyDescriptor ipd2) { if (ipd1.getClass0().isAssignableFrom(ipd2.getClass0())) { return new IndexedPropertyDescriptor(ipd1, ipd2); } else { return new IndexedPropertyDescriptor(ipd2, ipd1); } } /** * @return An array of EventSetDescriptors describing the kinds of * events fired by the target bean. */ private EventSetDescriptor[] getTargetEventInfo() throws IntrospectionException { if (events == null) { events = new HashMap<>(); } // Check if the bean has its own BeanInfo that will provide // explicit information. EventSetDescriptor[] explicitEvents = null; if (explicitBeanInfo != null) { explicitEvents = explicitBeanInfo.getEventSetDescriptors(); int ix = explicitBeanInfo.getDefaultEventIndex(); if (ix >= 0 && ix < explicitEvents.length) { defaultEventName = explicitEvents[ix].getName(); } } if (explicitEvents == null && superBeanInfo != null) { // We have no explicit BeanInfo events. Check with our parent. EventSetDescriptor[] supers = superBeanInfo.getEventSetDescriptors(); for (int i = 0; i < supers.length; i++) { addEvent(supers[i]); } int ix = superBeanInfo.getDefaultEventIndex(); if (ix >= 0 && ix < supers.length) { defaultEventName = supers[ix].getName(); } } for (int i = 0; i < additionalBeanInfo.length; i++) { EventSetDescriptor[] additional = additionalBeanInfo[i].getEventSetDescriptors(); if (additional != null) { for (int j = 0; j < additional.length; j++) { addEvent(additional[j]); } } } if (explicitEvents != null) { // Add the explicit explicitBeanInfo data to our results. for (int i = 0; i < explicitEvents.length; i++) { addEvent(explicitEvents[i]); } } else { // Apply some reflection to the current class. for (Map.Entry<String, EventSetInfo> entry : ClassInfo.get(this.beanClass).getEventSets().entrySet()) { // generate a list of Method objects for each of the target methods: List<Method> methods = new ArrayList<>(); for (Method method : ClassInfo.get(entry.getValue().getListenerType()).getMethods()) { if (isEventHandler(method)) { methods.add(method); } } addEvent(new EventSetDescriptor(entry.getKey(), entry.getValue(), methods.toArray(new Method[methods.size()]))); } JavaBean annotation = this.beanClass.getAnnotation(JavaBean.class); if ((annotation != null) && !annotation.defaultEventSet().isEmpty()) { this.defaultEventName = annotation.defaultEventSet(); } } EventSetDescriptor[] result; if (events.size() == 0) { result = EMPTY_EVENTSETDESCRIPTORS; } else { // Allocate and populate the result array. result = new EventSetDescriptor[events.size()]; result = events.values().toArray(result); // Set the default index. if (defaultEventName != null) { for (int i = 0; i < result.length; i++) { if (defaultEventName.equals(result[i].getName())) { defaultEventIndex = i; } } } } return result; } private void addEvent(EventSetDescriptor esd) { String key = esd.getName(); if (esd.getName().equals("propertyChange")) { propertyChangeSource = true; } EventSetDescriptor old = events.get(key); if (old == null) { events.put(key, esd); return; } EventSetDescriptor composite = new EventSetDescriptor(old, esd); events.put(key, composite); } /** * @return An array of MethodDescriptors describing the private * methods supported by the target bean. */ private MethodDescriptor[] getTargetMethodInfo() { if (methods == null) { methods = new HashMap<>(100); } // Check if the bean has its own BeanInfo that will provide // explicit information. MethodDescriptor[] explicitMethods = null; if (explicitBeanInfo != null) { explicitMethods = explicitBeanInfo.getMethodDescriptors(); } if (explicitMethods == null && superBeanInfo != null) { // We have no explicit BeanInfo methods. Check with our parent. MethodDescriptor[] supers = superBeanInfo.getMethodDescriptors(); for (int i = 0; i < supers.length; i++) { addMethod(supers[i]); } } for (int i = 0; i < additionalBeanInfo.length; i++) { MethodDescriptor[] additional = additionalBeanInfo[i].getMethodDescriptors(); if (additional != null) { for (int j = 0; j < additional.length; j++) { addMethod(additional[j]); } } } if (explicitMethods != null) { // Add the explicit explicitBeanInfo data to our results. for (int i = 0; i < explicitMethods.length; i++) { addMethod(explicitMethods[i]); } } else { // Apply some reflection to the current class. for (Method method : ClassInfo.get(this.beanClass).getMethods()) { addMethod(new MethodDescriptor(method)); } } // Allocate and populate the result array. MethodDescriptor[] result = new MethodDescriptor[methods.size()]; result = methods.values().toArray(result); return result; } private void addMethod(MethodDescriptor md) { // We have to be careful here to distinguish method by both name // and argument lists. // This method gets called a *lot, so we try to be efficient. String name = md.getName(); MethodDescriptor old = methods.get(name); if (old == null) { // This is the common case. methods.put(name, md); return; } // We have a collision on method names. This is rare. // Check if old and md have the same type. String[] p1 = md.getParamNames(); String[] p2 = old.getParamNames(); boolean match = false; if (p1.length == p2.length) { match = true; for (int i = 0; i < p1.length; i++) { if (p1[i] != p2[i]) { match = false; break; } } } if (match) { MethodDescriptor composite = new MethodDescriptor(old, md); methods.put(name, composite); return; } // We have a collision on method names with different type signatures. // This is very rare. String longKey = makeQualifiedMethodName(name, p1); old = methods.get(longKey); if (old == null) { methods.put(longKey, md); return; } MethodDescriptor composite = new MethodDescriptor(old, md); methods.put(longKey, composite); } /** * Creates a key for a method in a method cache. */ private static String makeQualifiedMethodName(String name, String[] params) { StringBuilder sb = new StringBuilder(name); sb.append('='); for (int i = 0; i < params.length; i++) { sb.append(':'); sb.append(params[i]); } return sb.toString(); } private int getTargetDefaultEventIndex() { return defaultEventIndex; } private int getTargetDefaultPropertyIndex() { return defaultPropertyIndex; } private BeanDescriptor getTargetBeanDescriptor() { // Use explicit info, if available, if (explicitBeanInfo != null) { BeanDescriptor bd = explicitBeanInfo.getBeanDescriptor(); if (bd != null) { return (bd); } } // OK, fabricate a default BeanDescriptor. return new BeanDescriptor(this.beanClass, findCustomizerClass(this.beanClass)); } private static Class<?> findCustomizerClass(Class<?> type) { String name = type.getName() + "Customizer"; try { type = ClassFinder.findClass(name, type.getClassLoader()); // Each customizer should inherit java.awt.Component and implement java.beans.Customizer // according to the section 9.3 of JavaBeans™ specification if (Component.class.isAssignableFrom(type) && Customizer.class.isAssignableFrom(type)) { return type; } } catch (Exception exception) { // ignore any exceptions } return null; } private boolean isEventHandler(Method m) { // We assume that a method is an event handler if it has a single // argument, whose type inherit from java.util.Event. Type[] argTypes = m.getGenericParameterTypes(); if (argTypes.length != 1) { return false; } return isSubclass(TypeResolver.erase(TypeResolver.resolveInClass(beanClass, argTypes[0])), EventObject.class); } //====================================================================== // Package private support methods. //====================================================================== /** * Internal support for finding a target methodName with a given * parameter list on a given class. */ private static Method internalFindMethod(Class<?> start, String methodName, int argCount, Class<?>[] args) { // For overriden methods we need to find the most derived version. // So we start with the given class and walk up the superclass chain. for (Class<?> cl = start; cl != null; cl = cl.getSuperclass()) { for (Method method : ClassInfo.get(cl).getMethods()) { // make sure method signature matches. if (method.getName().equals(methodName)) { Type[] params = method.getGenericParameterTypes(); if (params.length == argCount) { if (args != null) { boolean different = false; if (argCount > 0) { for (int j = 0; j < argCount; j++) { if (TypeResolver .erase(TypeResolver.resolveInClass(start, params[j])) != args[j]) { different = true; continue; } } if (different) { continue; } } } return method; } } } } // Now check any inherited interfaces. This is necessary both when // the argument class is itself an interface, and when the argument // class is an abstract class. Class<?>[] ifcs = start.getInterfaces(); for (int i = 0; i < ifcs.length; i++) { // Note: The original implementation had both methods calling // the 3 arg method. This is preserved but perhaps it should // pass the args array instead of null. Method method = internalFindMethod(ifcs[i], methodName, argCount, null); if (method != null) { return method; } } return null; } /** * Find a target methodName on a given class. */ static Method findMethod(Class<?> cls, String methodName, int argCount) { return findMethod(cls, methodName, argCount, null); } /** * Find a target methodName with specific parameter list on a given class. * <p> * Used in the contructors of the EventSetDescriptor, * PropertyDescriptor and the IndexedPropertyDescriptor. * <p> * @param cls The Class object on which to retrieve the method. * @param methodName Name of the method. * @param argCount Number of arguments for the desired method. * @param args Array of argument types for the method. * @return the method or null if not found */ static Method findMethod(Class<?> cls, String methodName, int argCount, Class<?>[] args) { if (methodName == null) { return null; } return internalFindMethod(cls, methodName, argCount, args); } /** * Return true if class a is either equivalent to class b, or * if class a is a subclass of class b, i.e. if a either "extends" * or "implements" b. * Note tht either or both "Class" objects may represent interfaces. */ static boolean isSubclass(Class<?> a, Class<?> b) { // We rely on the fact that for any given java class or // primtitive type there is a unqiue Class object, so // we can use object equivalence in the comparisons. if (a == b) { return true; } if (a == null || b == null) { return false; } for (Class<?> x = a; x != null; x = x.getSuperclass()) { if (x == b) { return true; } if (b.isInterface()) { Class<?>[] interfaces = x.getInterfaces(); for (int i = 0; i < interfaces.length; i++) { if (isSubclass(interfaces[i], b)) { return true; } } } } return false; } /** * Try to create an instance of a named class. * First try the classloader of "sibling", then try the system * classloader then the class loader of the current Thread. */ @SuppressWarnings("deprecation") static Object instantiate(Class<?> sibling, String className) throws InstantiationException, IllegalAccessException, NoSuchMethodException, InvocationTargetException, ClassNotFoundException { // First check with sibling's classloader (if any). ClassLoader cl = sibling.getClassLoader(); Class<?> cls = ClassFinder.findClass(className, cl); return cls.newInstance(); } } // end class Introspector //=========================================================================== /** * Package private implementation support class for Introspector's * internal use. * <p> * Mostly this is used as a placeholder for the descriptors. */ class GenericBeanInfo extends SimpleBeanInfo { private BeanDescriptor beanDescriptor; private EventSetDescriptor[] events; private int defaultEvent; private PropertyDescriptor[] properties; private int defaultProperty; private MethodDescriptor[] methods; private Reference<BeanInfo> targetBeanInfoRef; public GenericBeanInfo(BeanDescriptor beanDescriptor, EventSetDescriptor[] events, int defaultEvent, PropertyDescriptor[] properties, int defaultProperty, MethodDescriptor[] methods, BeanInfo targetBeanInfo) { this.beanDescriptor = beanDescriptor; this.events = events; this.defaultEvent = defaultEvent; this.properties = properties; this.defaultProperty = defaultProperty; this.methods = methods; this.targetBeanInfoRef = (targetBeanInfo != null) ? new SoftReference<>(targetBeanInfo) : null; } /** * Package-private dup constructor * This must isolate the new object from any changes to the old object. */ GenericBeanInfo(GenericBeanInfo old) { beanDescriptor = new BeanDescriptor(old.beanDescriptor); if (old.events != null) { int len = old.events.length; events = new EventSetDescriptor[len]; for (int i = 0; i < len; i++) { events[i] = new EventSetDescriptor(old.events[i]); } } defaultEvent = old.defaultEvent; if (old.properties != null) { int len = old.properties.length; properties = new PropertyDescriptor[len]; for (int i = 0; i < len; i++) { PropertyDescriptor oldp = old.properties[i]; if (oldp instanceof IndexedPropertyDescriptor) { properties[i] = new IndexedPropertyDescriptor((IndexedPropertyDescriptor) oldp); } else { properties[i] = new PropertyDescriptor(oldp); } } } defaultProperty = old.defaultProperty; if (old.methods != null) { int len = old.methods.length; methods = new MethodDescriptor[len]; for (int i = 0; i < len; i++) { methods[i] = new MethodDescriptor(old.methods[i]); } } this.targetBeanInfoRef = old.targetBeanInfoRef; } public PropertyDescriptor[] getPropertyDescriptors() { return properties; } public int getDefaultPropertyIndex() { return defaultProperty; } public EventSetDescriptor[] getEventSetDescriptors() { return events; } public int getDefaultEventIndex() { return defaultEvent; } public MethodDescriptor[] getMethodDescriptors() { return methods; } public BeanDescriptor getBeanDescriptor() { return beanDescriptor; } public java.awt.Image getIcon(int iconKind) { BeanInfo targetBeanInfo = getTargetBeanInfo(); if (targetBeanInfo != null) { return targetBeanInfo.getIcon(iconKind); } return super.getIcon(iconKind); } private BeanInfo getTargetBeanInfo() { if (this.targetBeanInfoRef == null) { return null; } BeanInfo targetBeanInfo = this.targetBeanInfoRef.get(); if (targetBeanInfo == null) { targetBeanInfo = ThreadGroupContext.getContext().getBeanInfoFinder() .find(this.beanDescriptor.getBeanClass()); if (targetBeanInfo != null) { this.targetBeanInfoRef = new SoftReference<>(targetBeanInfo); } } return targetBeanInfo; } }