JavaWeb 报错记录

古城微笑少年丶 2022-04-18 05:39 509阅读 0赞

### 一.Could not autowire field ###

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'pictureController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.service.PictureService com.controller.PictureController.pictureService; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type \[com.service.PictureService\] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations:\{@org.springframework.beans.factory.annotation.Autowired(required=true)\}

在Controller中使用了AutoWired注解，注入service属性 pictureService，报错信息：找不到这个service,原因是在service层忘记加上@Service注解,加上即可

### 二.http://java.sun.com/jsp/jstl/core cannot be resolved ###

org.apache.jasper.JasperException: The absolute uri: http://java.sun.com/jsp/jstl/core cannot be resolved in either web.xml or the jar files deployed with this application

根本原因是web项目用了jsp,而jsp中使用了jstl，但是却没有引入jar包，jstl有1.1和1.2的版本，确定自己缺少的是什么版本，我是少了jstl1.2.jar

经测试下面两种方法都可以解决，我用了第二种  
1.在WEB-INF/lib下拷贝一个jstl1.2.jar  
2.在pom.xml中加入jstl的依赖：  
<dependency>  
<groupId>jstl</groupId>  
<artifactId>jstl</artifactId>  
<version>1.2</version>  
</dependency>

### 三.java.util.concurrent.ExecutionException: ###

java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component \[StandardEngine\[Tomcat\].StandardHost\[localhost\].StandardContext\[\]\]

可能原因是在web.xml中配置<servlet-mapping>时，  <url-pattern>属性配置错误  
我写的是  <url-pattern>\*.html/</url-pattern>，其实应该没有/，  改成这样就不报错了<url-pattern>\*.html</url-pattern>

### 四.前端传参和controller形参表不一致，导致null ###

严重: Servlet.service() for servlet \[spring-manager\] in context with path \[\] threw exception \[Request processing failed; nested exception is java.lang.NullPointerException\] with root cause java.lang.NullPointerException   
at com.net.controller.ConMakerController.createConMaker(ConMakerController.java:33)

前端传参：url：/create，参数：**parentId**

$.post("/create",\{parentId:node.parentId\},function(data)\{......\});

java-Controller:

@RequestMapping("/create")  
public boolean createConMaker(Long **parentid**) \{  
      dosometing() .......  
 \}

两个parentid要对应上，形参表里是小写的id,所以在这里接收到的parentid是null,故报错如上，改成parentId，大写的即可

### 五.406错误 ###

406是HTTP协议状态码的一种，表示无法使用请求的特性来响应请求的网页。一般指客户端浏览器不接受所请求页面的MIME类型

1、json所依赖的jar包不存在。一般是jackson  
2、spring和jackson版本对不上：  
如果是使用的spring 4.0.\*的话，可以引入jackson1.9.\*的包   
如果是使用的spring4.1.\*的话，可以引入jackson2.7.\*的。  
3、请求的后缀是.html的，返回的格式是json的  
如果是以html为后缀的url发起请求，然后@ResponseBody返回时转换成json，就会报406.

### 六.配置文件没有复制到target/classes文件加下 ###

org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): cn.kevin.search.mapper.ItemMapper.getItemList  
    at org.apache.ibatis.binding.MapperMethod$SqlCommand.<init>(MapperMethod.java:189)  
    at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:43)  
    at org.apache.ibatis.binding.MapperProxy.cachedMapperMethod(MapperProxy.java:58)

这个报错是由于，itemMapper.xml在src/main/java目录下，而Eclipse在build的时候，默认只会把src/main/resources下面的配置文件复制到classes下，而src/main/java目录下则只会复制.java文件生成的.class文件。所以漏掉了在src/main/java目录下的itemMapper.xml文件，所以报错。

解决方法就在pom.xml下加入bulid即可：

<build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                    <includes>
                        <include>**/*.properties</include>
                        <include>**/*.xml</include>
                    </includes>
                    <filtering>false</filtering>
            </resource>
        </resources>
    </build>

修改后在运行，还是报错：

严重: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener  
org.springframework.beans.factory.BeanDefinitionStoreException: Could not resolve bean definition resource pattern \[classpath:spring/applicationContext\*.xml\]; nested exception is java.io.FileNotFoundException: class path resource \[spring/\] cannot be resolved to URL because it does not exist   at  org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:229)

找不到spring/applicationContext\*.xml 配置文件。。

查看target/classes目录，发现上面的itemMapper.xml是有了，但是src/main/resources下面的配置文件却没有了。。可能是由于配置了上面的build节点，导致只复制了src/main/java下的配置文件，既然这样，那就在修改下pom.xml：

<resources>
        <resource>
            <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
            <filtering>false</filtering>
        </resource>
        <resource>
            <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
            <filtering>false</filtering>
        </resource> 
    </resources>

在上面的基础上，添加上src/main/resources的配置

### 7.jsp中调用   <li class="item-book" bookid="11078102">       <div class="p-img">           <a target="\_blank" href="/item/$\{item.id \}.html">               <img width="160" height="160" data-img="1" data-lazyload="$\{ item.images\[0\]\}" />           </a>       </div> ###

jsp中item.images\[0\] 为什么能调用到java，Item实体类中的  
    public String\[\] getImages() \{  
        if(image!=null) \{  
            String\[\] images=image.split(",");  
            return images;  
        \}  
        return null;  
    \}

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为什么model设置model.addAttribute("query", “苹果CR”);，能直接返回jsp，然后在jsp中能显示相关的信息苹果CR

### 8.SpringBoot2.1.5创建项目 ###

配置完application.yml后运行不起来报错：

Failed to bind properties under 'spring.datasource.type' to java.lang.Class<javax.sql.DataSource>:  
    Property: spring.datasource.type  
    Value: org.apache.tomcat.jdbc.pool.DataSource  
    Origin: class path resource \[application.properties\]:5:24  
    Reason: No converter found capable of converting from type \[java.lang.String\] to type \[java.lang.Class<javax.sql.DataSource>\]

Action:  
Update your application's configuration

解决:在pom.xml中加入log4j的依赖

<dependency>
    	<groupId>log4j</groupId>
    	<artifactId>log4j</artifactId>
    	<version>1.2.16</version>
    	<scope>compile</scope>
    </dependency>

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