我在 app-context.xml 文件中有以下bean定义：
deleteButton我尝试通过代码手动创建addNewButton和 String[] contextPaths = new String[] {"todo/app-context.xml"};
ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext(contextPaths);
ActionListenerButton addNewButton = new ActionListenerButton();
addNewButton.setText("Add New");
System.out.println("setText(Add New)");
ListTableActionListener addActionListener = (ListTableActionListener) ctx.getBean("addNewButtonActionListener");
addNewButton.setActionListener(addActionListener);
ActionListenerButton deleteButton = new ActionListenerButton();
deleteButton.setText("Delete");
System.out.println("setText(Delete)");
ActionListener deleteActionListener = (ActionListener) ctx.getBean("addNewButtonActionListener");
deleteButton.setActionListener(deleteActionListener);
AutowireCapableBeanFactory factory = ctx.getAutowireCapableBeanFactory();
factory.autowireBean(addNewButton);
factory.initializeBean(addNewButton, "addNewButton");
factory.autowireBean(deleteButton);
factory.initializeBean(deleteButton, "deleteButton");
bean：
addNewButtonActionListener豆addNewButtonActionListener和deleteButton，addNewButton和@Component("addNewButtonActionListener")
public class AddNewButtonActionListener extends ListTableActionListener {
@Resource(name="itemList")
public void setList(List list) {
this.list = list;
}
@Resource(name="itemTable")
public void setTable(JTable itemTable) {
this.itemTable = itemTable;
}
public void actionPerformed(ActionEvent e) {
list.add("New Item");
itemTable.revalidate();
}
}
bean依赖，使用注释定义：
@Component("deleteButtonActionListener")
public class DeleteButtonActionListener extends ListTableActionListener {
@Resource(name="itemList")
public void setList(List list) {
this.list = list;
}
@Resource(name="itemTable")
public void setTable(JTable itemTable) {
this.itemTable = itemTable;
}
public void actionPerformed(ActionEvent e) {
int selectedRow = itemTable.getSelectedRow();
if (selectedRow == -1) {
// if there is no selected row, don't do anything
return;
}
if (itemTable.isEditing()) {
// if we are editing the table, don't do anything
return;
}
if (selectedRow < list.size()) {
list.remove(selectedRow);
itemTable.revalidate();
}
}
}
ActionListenerButton public class ActionListenerButton extends JButton {
String text;
public String getText() {
return text;
}
public void setText(String text) {
this.text = text;
}
private ActionListener actionListener;
public void setActionListener(ActionListener actionListener) {
this.actionListener = actionListener;
}
public ActionListener getActionListener() {
return actionListener;
}
public void init() {
this.addActionListener(actionListener);
}
}
类看起来像这样：
buttonPanel但似乎bean addNewButton（在xml中定义）是在deleteButton和NoSuchBeanDefinitionException bean之前创建的（应该由工厂，代码初始化），因为我得到了13:15:33.524 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating instance of bean 'org.springframework.context.event.internalEventListenerFactory'
13:15:33.524 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Eagerly caching bean 'org.springframework.context.event.internalEventListenerFactory' to allow for resolving potential circular references
13:15:33.526 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Finished creating instance of bean 'org.springframework.context.event.internalEventListenerFactory'
13:15:33.526 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating shared instance of singleton bean 'mainFrame'
13:15:33.526 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating instance of bean 'mainFrame'
13:15:33.543 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Eagerly caching bean 'mainFrame' to allow for resolving potential circular references
13:15:33.558 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating shared instance of singleton bean 'mainPanel'
13:15:33.558 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating instance of bean 'mainPanel'
13:15:33.563 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Eagerly caching bean 'mainPanel' to allow for resolving potential circular references
13:15:33.577 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating shared instance of singleton bean 'itemScrollPane'
13:15:33.577 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating instance of bean 'itemScrollPane'
13:15:33.581 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Returning cached instance of singleton bean 'itemTable'
13:15:33.598 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Eagerly caching bean 'itemScrollPane' to allow for resolving potential circular references
13:15:33.604 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Finished creating instance of bean 'itemScrollPane'
13:15:33.605 [main] WARN o.s.c.s.ClassPathXmlApplicationContext - Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mainFrame' defined in class path resource [todo/app-context.xml]: Cannot resolve reference to bean 'mainPanel' while setting bean property 'mainPanel'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mainPanel' defined in class path resource [todo/app-context.xml]: Cannot resolve reference to bean 'buttonPanel' while setting bean property 'panelComponents' with key [1]; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'deleteButton' available
13:15:33.605 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@77f99a05: defining beans [addNewButtonActionListener,deleteButtonActionListener,itemTableModel,org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnnotationProcessor,org.springframework.context.event.internalEventListenerProcessor,org.springframework.context.event.internalEventListenerFactory,mainFrame,mainPanel,itemScrollPane,itemTable,buttonPanel,itemList]; root of factory hierarchy
13:15:33.605 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Retrieved dependent beans for bean 'itemList': [addNewButtonActionListener, itemTableModel, deleteButtonActionListener]
13:15:33.606 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Retrieved dependent beans for bean 'itemTableModel': [itemTable]
13:15:33.606 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Retrieved dependent beans for bean 'itemTable': [deleteButtonActionListener, itemScrollPane]
13:15:33.606 [main] DEBUG o.s.b.f.s.DisposableBeanAdapter - Invoking destroy() on bean with name 'itemList'
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mainFrame' defined in class path resource [todo/app-context.xml]: Cannot resolve reference to bean 'mainPanel' while setting bean property 'mainPanel'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mainPanel' defined in class path resource [todo/app-context.xml]: Cannot resolve reference to bean 'buttonPanel' while setting bean property 'panelComponents' with key [1]; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'deleteButton' available
包含描述＆＃34;没有名为＆＃39; deleteButton＆＃39;可用＆＃34; ：
deleteButton如何让Spring在addNewButton bean之前实例化buttonPanel和<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd
http://www.springframework.org/schema/util
http://www.springframework.org/schema/util/spring-util.xsd">
<context:component-scan base-package="todo"/>
<bean id="mainFrame" class="todo.ui.MainFrame" init-method="init">
<property name="mainPanel">
<ref bean="mainPanel"/>
</property>
<property name="title">
<value>My To Do List</value>
</property>
</bean>
<bean id="mainPanel" class="todo.ui.BoxLayoutPanel"
init-method="init">
<property name="axis">
<!-- "1" corresponds to BoxLayout.Y_AXIS
Spring can access constants, but it's more complex -->
<value>1</value>
</property>
<property name="panelComponents">
<list>
<ref bean="itemScrollPane"/>
<ref bean="buttonPanel"/>
</list>
</property>
</bean>
<bean id="itemScrollPane" class="javax.swing.JScrollPane">
<constructor-arg>
<ref bean="itemTable"/>
</constructor-arg>
</bean>
<bean id="itemTable" class="javax.swing.JTable" depends-on="itemTableModel">
<property name="model">
<ref bean="itemTableModel"/>
</property>
</bean>
<bean id="buttonPanel" class="todo.ui.BoxLayoutPanel" init-method="init" depends-on="deleteButton">
<property name="axis">
<!-- "0" corresponds to BoxLayout.X_AXIS -->
<value>0</value>
</property>
<property name="panelComponents">
<list>
<ref bean="deleteButton"/>
<ref bean="addNewButton"/>
</list>
</property>
</bean>
<!-- <bean id="deleteButton" class="todo.ui.button.ActionListenerButton"
init-method="init">
<property name="actionListener">
<ref bean="deleteButtonActionListener"/>
</property>
<property name="text">
<value>Delete</value>
</property>
</bean> -->
<!-- <bean id="deleteButtonActionListener"
class="todo.ui.button.DeleteButtonActionListener">
<property name="list">
<ref bean="itemList"/>
</property>
<property name="table">
<ref bean="itemTable"/>
</property>
</bean> -->
<!-- <bean id="addNewButton" class="todo.ui.button.ActionListenerButton"
init-method="init">
<property name="actionListener">
<ref bean="addNewButtonActionListener"/>
</property>
<property name="text">
<value>Add New</value>
</property>
</bean> -->
<!-- <bean id="addNewButtonActionListener"
class="todo.ui.button.AddNewButtonActionListener">
<property name="list">
<ref bean="itemList"/>
</property>
<property name="table">
<ref bean="itemTable"/>
</property>
</bean> -->
<util:list id="itemList">
<value>Item 1</value>
<value>Item 2</value>
<value>Item 3</value>
</util:list>
</beans>
bean？
P.S。完整 app-context.xml 现在看起来像这样：
AutowireCapableBeanFactoryUPD
或许我错了，我的代码lazy-init="true"并没有真正创建bean并将它们添加到Spring容器中......
因为我在xml中将mainFrame属性添加到mainPanel，buttonPanel和mainFrame bean，并在带有工厂的代码后调用了AutowireCapableBeanFactory factory = ctx.getAutowireCapableBeanFactory();
factory.autowireBean(addNewButton);
factory.initializeBean(addNewButton, "addNewButton");
factory.autowireBean(deleteButton);
factory.initializeBean(deleteButton, "deleteButton");
ctx.getBean("mainFrame");
：
14:04:49.780 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Returning cached instance of singleton bean 'lifecycleProcessor'
14:04:49.783 [main] DEBUG o.s.c.e.PropertySourcesPropertyResolver - Could not find key 'spring.liveBeansView.mbeanDomain' in any property source
setText(Add New)
14:04:49.785 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Returning cached instance of singleton bean 'addNewButtonActionListener'
setText(Delete)
14:04:49.786 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Returning cached instance of singleton bean 'deleteButtonActionListener'
14:04:49.812 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating shared instance of singleton bean 'mainFrame'
14:04:49.812 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating instance of bean 'mainFrame'
14:04:49.828 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Eagerly caching bean 'mainFrame' to allow for resolving potential circular references
14:04:49.846 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating shared instance of singleton bean 'mainPanel'
14:04:49.846 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating instance of bean 'mainPanel'
14:04:49.850 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Eagerly caching bean 'mainPanel' to allow for resolving potential circular references
14:04:49.869 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Returning cached instance of singleton bean 'itemScrollPane'
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mainFrame' defined in class path resource [todo/app-context.xml]: Cannot resolve reference to bean 'mainPanel' while setting bean property 'mainPanel'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mainPanel' defined in class path resource [todo/app-context.xml]: Cannot resolve reference to bean 'buttonPanel' while setting bean property 'panelComponents' with key [1]; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'deleteButton' available
我在控制台中获得以下输出：
addNewButtonActionListener即，Spring只返回单例bean deleteButtonActionListener和addNewButton的缓存实例，bot不会创建并返回bean deleteButton和<?php
$servername = '10.4.41.164:3306';
$username = 'admin';
$password = 'admin';
$db = 'AssistMe';
echo "Pepito";
// Create connection
$conn = mysqli_connect($servername, $username, $password);
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
} else {
echo "Connected succesfully";
}
?>
的实例。< / p>
答案 0 :(得分：0)
我在related SO question找到了答案。更改代码后：
AutowireCapableBeanFactory factory = ctx.getAutowireCapableBeanFactory();
BeanDefinition definition = new RootBeanDefinition(ActionListenerButton.class);
BeanDefinitionRegistry registry = (BeanDefinitionRegistry) factory;
registry.registerBeanDefinition("addNewButton", definition);
registry.registerBeanDefinition("deleteButton", definition);
factory.initializeBean(addNewButton, "addNewButton");
factory.initializeBean(deleteButton, "deleteButton");
应用程序已成功启动。