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ssm框架中requestbody返回数据是否可以返回类

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1

SSM

class="cursor-pointer"> 详细描述

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spring进行代码注入的方式，通过标签注入与注解注入有什么不同？

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1

spring mybatis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

   <!--spring和mybatis整合-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean" >
        <property name="dataSource" ref="datasource"/>
        <property name="mapperLocations" value="StudentMapper.xml"/>
    </bean>

     <!--DAO接口所在包，Spring会自动寻找其路径下的接口 -->
    <bean id="studentDao" class="org.mybatis.spring.mapper.MapperScannerConfigurer" autowire="byName">
        <property name="basePackage" value="xiuzhenyuan.dao" />
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
    </bean>

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spring注入问题

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1

spring

class="cursor-pointer"> 详细描述

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实体表关系表，表之间的关系。

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1

class="cursor-pointer"> 详细描述

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nginx启动成功无法访问端口

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1

Nginx

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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连接池连不上数据库

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1

数据库

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

import javax.sql.DataSource;

import org.apache.commons.dbcp2.BasicDataSourceFactory;

/**
* DBCP配置类
* @author SUN
*/
public class KCYDBCPUtil {

private static Properties properties = new Properties();
   private static DataSource dataSource;
   //加载DBCP配置文件
   static{
try{
            InputStream fis = new FileInputStream("config/dbcp.properties");
           properties.load(fis);
       }catch(IOException e){
System.out.println("出错啦啦啦啦啦");
           e.printStackTrace();
       }

try{
dataSource = BasicDataSourceFactory.createDataSource(properties);
       }catch(Exception e){
e.printStackTrace();
       }
}

//从连接池中获取一个连接
   public static Connection getConnection(){
Connection connection = null;
       try {
connection = dataSource.getConnection();
           connection.setAutoCommit(false);
       } catch (SQLException e) {
e.printStackTrace();
       }
return connection;
   }

public static void main(String[] args) {
getConnection();
   }
}

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spring jdbc

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1

JDBC

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 源码

java.lang.NullPointerException
	at com.spring.test.TestDemo.fun2(TestDemo.java:36)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:532)
	at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:115)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:171)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:167)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:114)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:59)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$4(NodeTestTask.java:108)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:98)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:74)
	at java.util.ArrayList.forEach(ArrayList.java:1257)
	at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$4(NodeTestTask.java:112)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:98)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:74)
	at java.util.ArrayList.forEach(ArrayList.java:1257)
	at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$4(NodeTestTask.java:112)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:98)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:74)
	at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
	at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
	at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:220)
	at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:188)
	at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:202)
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:181)
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128)
	at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:74)
	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

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Tomcat提交表单报错

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1

mybatis spring

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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tomcat发布的项目，url访问路由控制器时不会触发控制器中连接点

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1

aop

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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jsp中from表单input输入值传递到后台的问题

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1

SSM

class="cursor-pointer"> 详细描述

获取的传值为String “{nowpage}”，而不是期待的input输入的内容 “5”。

没有报错，只是报的[WARN]。
后台无反应。
*@PathVariable("nowpage")int nowpage从url路径里（@RequestMapping(value = "/pages/{nowpage}/{pagesize}",method = RequestMethod.POST)）获取值的问题。
如果有师兄知道可能的错误请指教一下。（可能是配置的问题或者说是传递方式的问题，或者使用方法有问题）
1.在使用@PathVariable("nowpage")int nowpage的情况下，jsp需要用什么方式获取到input输入的值然后写入action或者url里（不使用js）。使“/page/{nowpage}”访问的时候变成“/page/5”（5是input输入的参数）
2.后台会提示下面警告：
[WARN]-[org.springframework.web.servlet.mvc.support.DefaultHandlerExceptionResolver] Failed to bind request element: org.springframework.web.method.annotation.MethodArgumentTypeMismatchException: Failed to convert value of type 'java.lang.String' to required type 'int'; nested exception is java.lang.NumberFormatException: For input string: "{nowpage}"
错误代码
jsp：
HTTP Status 400 – Bad Request
error：
Failed to convert value of type 'java.lang.String' to required type 'int'; nested exception is java.lang.NumberFormatException: For input string: "{nowpage}"

这里是字符串"{nowpage}" 用String接收也是"{nowpage}"，而不是期待的字符串类型 “5”

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

Controller：
  @RequestMapping(value = {"/pages/{nowpage}/{pagesize}","{/pages/{nowpage}}","{/pages}"},method = RequestMethod.POST)
    public String selectByPage(@PathVariable("nowpage")int nowpage,@PathVariable(value = "pagesize", required = false)int pagesize,Model model){……}

jsp：
<form class="navbar-form navbar-left" role="search"  action="/ptt/pages/{nowpage}/{pagesize}" id="pagefrom" name="pagefrom" method="POST">
        <div class="form-group">
            <input type="hidden" name="_method" value="POST"/>
            <input type="text" class="form-control" name="nowpage" id="nowpage"  />
            <input type="text" class="form-control" name="pagesize" id="pagesize"  />
        </div>
        <button type="submit" class="button btn-default" form="pagefrom" >page</button>
    </form>