Question

我是Spring和Hibernate概念的新手。我在简单的弹簧程序中使用集合。我的想法是将作者姓名，地址和ID存储到集合中。这是一个简单的弹簧框架，但我有一个错误。

弹簧model.xml

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

    <bean id="book" class="com.vishal.Book">
        <property name="author ">
            <list>
                <ref bean="book1 " />
                <ref bean="book2 " />
                <ref bean="book3 " />    
            </list>
        </property>
    </bean>

    <bean id="book1" class="com.vishal.Book">
        <property name="name" value="mark twain" />
        <property name="address" value="London" />
        <property name="id" value="230" />
    </bean>

    <bean id="book2" class="com.vishal.Book">
        <property name="name" value="gutav friedman" />
        <property name="address" value="Germany" />
        <property name="id" value="231" />
    </bean>

    <bean id="book3" class="com.vishal.Book">
        <property name="name" value=" Erastothe " />
        <property name="address" value="spain" />
        <property name="id" value="232" />
    </bean>

</beans>

主要班级

package com.vishal;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Springmain {

    @SuppressWarnings("resource")
    public static void main(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext(
                "spring-model.xml");
        Book book = (Book) context.getBean("book");
        book.authorName();
    }

}

book.java

package com.vishal;

import java.util.List;

public class Book {

    private List<Author> author;

    public List<Author> getAuthor() {
        return author;
    }

    public void setAuthor(List<Author> author) {
        this.author = author;
    }

    public void authorName() {
        for (Author authors : author)
            System.out.println(authors.getAddress() + authors.getId()
                    + authors.getName());
    }
}

作家类

package com.vishal;

public class Author {
    private String name;
    private String address;
    private int id;

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

以下是我得到的错误

Jun 10, 2013 11:29:36 AM org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@161d36b: startup date [Mon Jun 10 11:29:36 IST 2013]; root of context hierarchy
Jun 10, 2013 11:29:36 AM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [spring-model.xml]
Jun 10, 2013 11:29:37 AM org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons
INFO: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@1b5998f: defining beans [book,book1,book2,book3]; root of factory hierarchy
Jun 10, 2013 11:29:37 AM org.springframework.beans.factory.support.DefaultSingletonBeanRegistry destroySingletons
INFO: Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@1b5998f: defining beans [book,book1,book2,book3]; root of factory hierarchy
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'book' defined in class path resource [spring-model.xml]: Cannot resolve reference to bean 'book1 ' while setting bean property 'author ' with key [0]; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'book1 ' is defined
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:329)
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:107)
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveManagedList(BeanDefinitionValueResolver.java:353)
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:154)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1393)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1134)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:522)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:461)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:626)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
    at com.vishal.Springmain.main(Springmain.java:10)
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'book1 ' is defined
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanDefinition(DefaultListableBeanFactory.java:568)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getMergedLocalBeanDefinition(AbstractBeanFactory.java:1102)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:278)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:323)
    ... 17 more

Answer 1

bean引用中有空格：

而实际的bean名称没有空格：

此外，Luiggi建议Bean定义需要更正。

请检查一下。

Answer 2

在Book课程中，您有List<Author>，但在 spring-model.xml 文件中，您引用了book1，book2和book3的实例Book，而不是来自Author的复制/粘贴过程，并且忘记了最重要的步骤：调整您粘贴的内容。

只是为了展示一个例子：

<bean id="book1" class="com.vishal.Book">

应该是

<bean id="book1" class="com.vishal.Author">

此外，您指的是其他使用

的bean

<ref bean="book1 " />

最后应该修剪一个空白区域。它应该是

<ref bean="book1" />

与 spring-model.xml 文件中的其他bookX引用类似。

春天没有这样的bean定义异常

2 个答案: