我想尝试与 MongoDB 的弹簧集成，为此我做了以下事情。但它不工作一些如何 MongoTemplate 实例未创建并抛出 java.lang.NullPointerException。这是我的 application-context.xml
<?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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<!-- Activate annotation configured components -->
<context:annotation-config/>
<!-- Scan components for annotations within the configured package -->
<context:component-scan base-package="com.jeroenreijn.mongodb.example">
<context:exclude-filter type="annotation" expression="org.springframework.context.annotation.Configuration"/>
</context:component-scan>
<!-- Factory bean that creates the Mongo instance -->
<bean id="mongo" class="com.mongodb.Mongo">
<constructor-arg name="host" value="127.0.0.1" />
<constructor-arg name="port" value="27017" />
</bean>
<!-- Define the MongoTemplate which handles connectivity with MongoDB -->
<bean id="mongoTemplate" class="org.springframework.data.mongodb.core.MongoTemplate" depends-on="mongo">
<constructor-arg name="mongo" ref="mongo"/>
<constructor-arg name="databaseName" value="firstMongoDB"/>
</bean>
<!-- Use this post processor to translate any MongoExceptions thrown in @Repository annotated classes -->
<bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>
</beans>
这是我的主要方法：
public class MainApplication {
/**
* This is a variable used for Logging purpose, I have used slf4j.
*/
final Logger LOGGER = LoggerFactory.getLogger(MainApplication.class);
@Autowired
MongoTemplate mongoTemplate;
public void savePerson(Person p) {
mongoTemplate.save(p);
}
public static void main(String[] args) {
Person p = new PersonImpl("1", "Ayushya", "Devmurari");
MainApplication ma = new MainApplication();
ma.savePerson(p);
ma.LOGGER.info("Person named : " + p.getName() + " with id : "
+ p.getId() + " is saved.");
}
}
这是我的模型课：
@Document(collection = "AnotherPersonCollection")
public class PersonImpl implements Person {
private String id;
private String name;
private String surname;
// Constructor
public PersonImpl() {
}
public PersonImpl(String id, String name, String surname) {
this.id = id;
this.name = name;
this.surname = surname;
}
@Override
public String getId() {
return id;
}
@Override
public void setId(String id) {
this.id = id;
}
@Override
public String getName() {
return name;
}
@Override
public void setName(String name) {
this.name = name;
}
@Override
public String getSurname() {
return surname;
}
@Override
public void setSurname(String surname) {
this.surname = surname;
}
@Override
public String toString() {
return "Person has name " + "Id :" + id + "\n" + name + " \n"
+ "surname :" + surname;
}
}
需要帮助我已经尝试了几个教程，例如 mkyong 和许多其他教程，并且我遇到了 NoBeanDefinitionFound 的“mongoTemplate”错误：所以我尝试了这个。
更新：这是我的 pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.discusit</groupId>
<artifactId>MongoDBAppTrail4</artifactId>
<packaging>jar</packaging>
<version>1.0</version>
<name>Trying to create MongoDBApp</name>
<url>http://maven.apache.org</url>
<dependencies>
<!-- Log4J -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.5</version>
</dependency>
<!-- Spring framework -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>3.2.2.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>3.2.2.RELEASE</version>
</dependency>
<!-- Spring Web -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>3.2.2.RELEASE</version>
</dependency>
<!-- mongodb java driver -->
<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
<version>2.11.0</version>
</dependency>
<!-- Spring data mongodb -->
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-mongodb</artifactId>
<version>1.2.0.RELEASE</version>
</dependency>
<dependency>
<groupId>cglib</groupId>
<artifactId>cglib</artifactId>
<version>2.2.2</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.0</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-eclipse-plugin</artifactId>
<version>2.9</version>
<configuration>
<downloadSources>true</downloadSources>
<downloadJavadocs>true</downloadJavadocs>
</configuration>
</plugin>
</plugins>
</build>
</project>
这是我的堆栈跟踪：
log4j:WARN No appenders could be found for logger (org.springframework.core.env.StandardEnvironment).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
Exception in thread "main" org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'mongoTemplate' 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.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1117)
at com.discusit.main.MainApplication.main(MainApplication.java:39)