Question

我是春天的初学者。

我现在正试图看看我是否可以测试RequestMapping，RequestBody，RequestResponse和RestTemplate。

我希望收到此对象作为回复：

public interface TestObject {
    public int getId();
    public String getValue();
}

@Component
public class TestObjectImpl {

    private int id;
    private String value;

    public TestObjectImpl(int id, String value){
        this.id = id;
        this.value = value;
    }

    public int getId(){
        return id;
    }

    public String getValue(){
        return value;
    }
}

但是，我得到了：

org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'int' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1486) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1104) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:835) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:741) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:189) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1193) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1095) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:761) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:866) ~[spring-context-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:542) ~[spring-context-4.3.8.RELEASE.jar:4.3.8.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:737) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:370) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:314) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1162) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1151) [spring-boot-1.5.3.RELEASE.jar:1.5.3.RELEASE]
at io.yclub.castr.ads_java.ApplicationServer.main(ApplicationServer.java:12) [main/:na]

所以，它说，

Description:
Parameter 0 of constructor in io.yclub.castr.ads_java.google.adwords.model.TestObjectImpl required a bean of type 'int' that could not be found.

Action:
Consider defining a bean of type 'int' in your configuration.

但是我如何真正为＆＃39; int＆＃39;？

创建bean定义

我做了什么？

//编辑

感谢KrishnaKuntala，这只是因为我没有默认的构造函数。

立即解决问题。

Answer 1

您可以注入简单属性，并可以使用@Value注释和占位符轻松访问属性：

@Component
public class TestObjectImpl {
    private int id;
    private String value;

    @Autowired
    public TestObjectImpl(@Value("${prop1}")int id, @Value("${prop2}")String value){
        this.id = id;
        this.value = value;
    }

    public int getId(){
        return id;
    }

    public String getValue(){
        return value;
    }
}

然后你需要将它们添加到applicationContext：

<context:property-placeholder .../>

请注意

如果使用默认构造函数修复它，则需要另一种机制来初始化bean，因此，如果要添加非arg构造函数而不是执行上一个构造函数，则必须知道自己在做什么。

Answer 2

您不需要仅使用默认的无参数构造函数来创建bean。在你的情况下：

1）如果您正在使用XML配置并且想要使用接受参数的构造函数，则需要使用constructor-arg元素指定它们，如下所示：

<bean id="SomeObject" class="com.package.SomeObject">
  <constructor-arg val="someVal"/>
  <constructor-arg val="anotherVal"/>
</bean>

2）如果你使用Java配置类，你需要这样的东西：

@Configuration
public class Config {
    @Bean
    public SomeObject someObject() {
        return new SomeObject(1, "default");
    }
}

请查看有关constructor injection in spring的有用文章。

Answer 3

请尝试在TestObjecImpl类中添加默认值（无参数构造函数）。

@Component
public class TestObjectImpl {

    private int id;
    private String value;

    public TestObjectImpl(){
    }

    public TestObjectImpl(int id, String value){
        this.id = id;
        this.value = value;
    }

    public int getId(){
        return id;
    }

    public String getValue(){
        return value;
    }
}

Answer 4

我正在使用spring web-flow，并且该类未加载，必须在config servlet xml中声明。

NoSuchBeanDefinitionException：没有类型＆＃39; int＆＃39;的限定bean

4 个答案: