beanutils.java

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		int firstParen = signature.indexOf("(");
		int lastParen = signature.indexOf(")");

		if (firstParen > -1 && lastParen == -1) {
			throw new IllegalArgumentException("Invalid method signature '" + signature +
					"': expected closing ')' for args list");
		}
		else if (lastParen > -1 && firstParen == -1) {
			throw new IllegalArgumentException("Invalid method signature '" + signature +
					"': expected opening '(' for args list");
		}
		else if (firstParen == -1 && lastParen == -1) {
			return findMethodWithMinimalParameters(clazz, signature);
		}
		else {
			String methodName = signature.substring(0, firstParen);
			String[] parameterTypeNames =
					StringUtils.commaDelimitedListToStringArray(signature.substring(firstParen + 1, lastParen));
			Class[] parameterTypes = new Class[parameterTypeNames.length];
			for (int i = 0; i < parameterTypeNames.length; i++) {
				String parameterTypeName = parameterTypeNames[i].trim();
				try {
					parameterTypes[i] = ClassUtils.forName(parameterTypeName, clazz.getClassLoader());
				}
				catch (Throwable ex) {
					throw new IllegalArgumentException("Invalid method signature: unable to resolve type [" +
							parameterTypeName + "] for argument " + i + ". Root cause: " + ex);
				}
			}
			return findMethod(clazz, methodName, parameterTypes);
		}
	}


	/**
	 * Retrieve the JavaBeans <code>PropertyDescriptor</code>s of a given class.
	 * @param clazz the Class to retrieve the PropertyDescriptors for
	 * @return an array of <code>PropertyDescriptors</code> for the given class
	 * @throws BeansException if PropertyDescriptor look fails
	 */
	public static PropertyDescriptor[] getPropertyDescriptors(Class clazz) throws BeansException {
		CachedIntrospectionResults cr = CachedIntrospectionResults.forClass(clazz);
		return cr.getBeanInfo().getPropertyDescriptors();
	}

	/**
	 * Retrieve the JavaBeans <code>PropertyDescriptors</code> for the given property.
	 * @param clazz the Class to retrieve the PropertyDescriptor for
	 * @param propertyName the name of the property
	 * @return the corresponding PropertyDescriptor, or <code>null</code> if none
	 * @throws BeansException if PropertyDescriptor lookup fails
	 */
	public static PropertyDescriptor getPropertyDescriptor(Class clazz, String propertyName)
			throws BeansException {

		CachedIntrospectionResults cr = CachedIntrospectionResults.forClass(clazz);
		return cr.getPropertyDescriptor(propertyName);
	}

	/**
	 * Find a JavaBeans <code>PropertyDescriptor</code> for the given method,
	 * with the method either being the read method or the write method for
	 * that bean property.
	 * @param method the method to find a corresponding PropertyDescriptor for
	 * @return the corresponding PropertyDescriptor, or <code>null</code> if none
	 * @throws BeansException if PropertyDescriptor lookup fails
	 */
	public static PropertyDescriptor findPropertyForMethod(Method method) throws BeansException {
		Assert.notNull(method, "Method must not be null");
		PropertyDescriptor[] pds = getPropertyDescriptors(method.getDeclaringClass());
		for (int i = 0; i < pds.length; i++) {
			PropertyDescriptor pd = pds[i];
			if (method.equals(pd.getReadMethod()) || method.equals(pd.getWriteMethod())) {
				return pd;
			}
		}
		return null;
	}

	/**
	 * Determine the bean property type for the given property from the
	 * given classes/interfaces, if possible.
	 * @param propertyName the name of the bean property
	 * @param beanClasses the classes to check against
	 * @return the property type, or <code>Object.class</code> as fallback
	 */
	public static Class findPropertyType(String propertyName, Class[] beanClasses) {
		if (beanClasses != null) {
			for (int i = 0; i < beanClasses.length; i++) {
				PropertyDescriptor pd = getPropertyDescriptor(beanClasses[i], propertyName);
				if (pd != null) {
					return pd.getPropertyType();
				}
			}
		}
		return Object.class;
	}

	/**
	 * Check if the given type represents a "simple" property:
	 * a primitive, a String, a Class, or a corresponding array.
	 * <p>Used to determine properties to check for a "simple" dependency-check.
	 * @param clazz the type to check
	 * @return whether the given type represent a "simple" property
	 * @see org.springframework.beans.factory.support.RootBeanDefinition#DEPENDENCY_CHECK_SIMPLE
	 * @see org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory#checkDependencies
	 */
	public static boolean isSimpleProperty(Class clazz) {
		Assert.notNull(clazz, "Class must not be null");
		return clazz.isPrimitive() || ClassUtils.isPrimitiveArray(clazz) ||
				ClassUtils.isPrimitiveWrapper(clazz) || ClassUtils.isPrimitiveWrapperArray(clazz) ||
				clazz.equals(String.class) || clazz.equals(String[].class) ||
				clazz.equals(Class.class) || clazz.equals(Class[].class);
	}

	/**
	 * Determine if the given target type is assignable from the given value
	 * type, assuming setting by reflection. Considers primitive wrapper
	 * classes as assignable to the corresponding primitive types.
	 * @param targetType the target type
	 * @param valueType the value type that should be assigned to the target type
	 * @return if the target type is assignable from the value type
	 * @deprecated as of Spring 2.0, in favor of <code>ClassUtils.isAssignable</code>
	 * @see org.springframework.util.ClassUtils#isAssignable(Class, Class)
	 */
	public static boolean isAssignable(Class targetType, Class valueType) {
		return ClassUtils.isAssignable(targetType, valueType);
	}

	/**
	 * Determine if the given type is assignable from the given value,
	 * assuming setting by reflection. Considers primitive wrapper classes
	 * as assignable to the corresponding primitive types.
	 * @param type the target type
	 * @param value the value that should be assigned to the type
	 * @return if the type is assignable from the value
	 * @deprecated as of Spring 2.0, in favor of <code>ClassUtils.isAssignableValue</code>
	 * @see org.springframework.util.ClassUtils#isAssignableValue(Class, Object)
	 */
	public static boolean isAssignable(Class type, Object value) {
		return ClassUtils.isAssignableValue(type, value);
	}


	/**
	 * Copy the property values of the given source bean into the target bean.
	 * <p>Note: The source and target classes do not have to match or even be derived
	 * from each other, as long as the properties match. Any bean properties that the
	 * source bean exposes but the target bean does not will silently be ignored.
	 * <p>This is just a convenience method. For more complex transfer needs,
	 * consider using a full BeanWrapper.
	 * @param source the source bean
	 * @param target the target bean
	 * @throws BeansException if the copying failed
	 * @see BeanWrapper
	 */
	public static void copyProperties(Object source, Object target) throws BeansException {
		copyProperties(source, target, null, null);
	}

	/**
	 * Copy the property values of the given source bean into the given target bean,
	 * only setting properties defined in the given "editable" class (or interface).
	 * <p>Note: The source and target classes do not have to match or even be derived
	 * from each other, as long as the properties match. Any bean properties that the
	 * source bean exposes but the target bean does not will silently be ignored.
	 * <p>This is just a convenience method. For more complex transfer needs,
	 * consider using a full BeanWrapper.
	 * @param source the source bean
	 * @param target the target bean
	 * @param editable the class (or interface) to restrict property setting to
	 * @throws BeansException if the copying failed
	 * @see BeanWrapper
	 */
	public static void copyProperties(Object source, Object target, Class editable)
			throws BeansException {

		copyProperties(source, target, editable, null);
	}

	/**
	 * Copy the property values of the given source bean into the given target bean,
	 * ignoring the given "ignoreProperties".
	 * <p>Note: The source and target classes do not have to match or even be derived
	 * from each other, as long as the properties match. Any bean properties that the
	 * source bean exposes but the target bean does not will silently be ignored.
	 * <p>This is just a convenience method. For more complex transfer needs,
	 * consider using a full BeanWrapper.
	 * @param source the source bean
	 * @param target the target bean
	 * @param ignoreProperties array of property names to ignore
	 * @throws BeansException if the copying failed
	 * @see BeanWrapper
	 */
	public static void copyProperties(Object source, Object target, String[] ignoreProperties)
			throws BeansException {

		copyProperties(source, target, null, ignoreProperties);
	}

	/**
	 * Copy the property values of the given source bean into the given target bean.
	 * <p>Note: The source and target classes do not have to match or even be derived
	 * from each other, as long as the properties match. Any bean properties that the
	 * source bean exposes but the target bean does not will silently be ignored.
	 * @param source the source bean
	 * @param target the target bean
	 * @param editable the class (or interface) to restrict property setting to
	 * @param ignoreProperties array of property names to ignore
	 * @throws BeansException if the copying failed
	 * @see BeanWrapper
	 */
	private static void copyProperties(Object source, Object target, Class editable, String[] ignoreProperties)
			throws BeansException {

		Assert.notNull(source, "Source must not be null");
		Assert.notNull(target, "Target must not be null");

		Class actualEditable = target.getClass();
		if (editable != null) {
			if (!editable.isInstance(target)) {
				throw new IllegalArgumentException("Target class [" + target.getClass().getName() +
						"] not assignable to Editable class [" + editable.getName() + "]");
			}
			actualEditable = editable;
		}
		PropertyDescriptor[] targetPds = getPropertyDescriptors(actualEditable);
		List ignoreList = (ignoreProperties != null) ? Arrays.asList(ignoreProperties) : null;

		for (int i = 0; i < targetPds.length; i++) {
			PropertyDescriptor targetPd = targetPds[i];
			if (targetPd.getWriteMethod() != null &&
					(ignoreProperties == null || (!ignoreList.contains(targetPd.getName())))) {
				PropertyDescriptor sourcePd = getPropertyDescriptor(source.getClass(), targetPd.getName());
				if (sourcePd != null && sourcePd.getReadMethod() != null) {
					try {
						Method readMethod = sourcePd.getReadMethod();
						if (!Modifier.isPublic(readMethod.getDeclaringClass().getModifiers())) {
							readMethod.setAccessible(true);
						}
						Object value = readMethod.invoke(source, new Object[0]);
						Method writeMethod = targetPd.getWriteMethod();
						if (!Modifier.isPublic(writeMethod.getDeclaringClass().getModifiers())) {
							writeMethod.setAccessible(true);
						}
						writeMethod.invoke(target, new Object[] {value});
					}
					catch (Throwable ex) {
						throw new FatalBeanException("Could not copy properties from source to target", ex);
					}
				}
			}
		}
	}

}