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ssm框架中requestbody返回数据是否可以返回类

0

1

SSM

class="cursor-pointer"> 详细描述

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批量插入用append字符串拼接,字段都核对过了,就是报错

1

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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找不到log4j的配置文件路径

1

class="cursor-pointer"> 详细描述

使用PropertyConfigurator.configure来加载配置文件时，无法找到log4j.properties的路径。

在进行log4j demo，部分代码如下：

public class TestLog4j {
    // 获取日志对象
    static Logger logger = Logger.getLogger(TestLog4j.class);

public static void main(String[] args) throws InterruptedException {
        // 加载配置文件
        PropertyConfigurator.configure("log4j.properties");

for (int i = 0;  i < 100; i++) {
            logger.trace("跟踪信息");
            logger.debug("调试信息");
            logger.info("输出信息");

Thread.sleep(100);

logger.warn("警告信息");
            logger.error("错误信息");
            logger.fatal("致命信息");
        }
    }
}
可以运行，但同时会遇到报错如下：

log4j:ERROR Could not read configuration file [log4j.properties].

java.io.FileNotFoundException: log4j.properties (No such file or directory)

at java.io.FileInputStream.open0(Native Method)

at java.io.FileInputStream.open(FileInputStream.java:195)

at java.io.FileInputStream.(FileInputStream.java:138)

at java.io.FileInputStream.(FileInputStream.java:93)

at org.apache.log4j.PropertyConfigurator.doConfigure(PropertyConfigurator.java:372)

at org.apache.log4j.PropertyConfigurator.configure(PropertyConfigurator.java:403)

at log4j.TestLog4j.main(TestLog4j.java:39)

log4j:ERROR Ignoring configuration file [log4j.properties].

DEBUG [main] (TestLog4j.java:43) - 调试信息

INFO [main] (TestLog4j.java:44) - 输出信息

WARN [main] (TestLog4j.java:48) - 警告信息

ERROR [main] (TestLog4j.java:49) - 错误信息

FATAL [main] (TestLog4j.java:50) - 致命信息

DEBUG [main] (TestLog4j.java:43) - 调试信息

找不到log4j的配置文件。

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

PropertyConfigurator.configure("log4j.properties");

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service层不能使用

0

1

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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Resin远程配置之后启动不了

0

1

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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为什么从jdbc.properties获取不到资源

1

mybatis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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加载配置文件出错

1

spring

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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tomcat安装配置好之后打不开

2

1

linux命令

class="cursor-pointer"> 详细描述

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浮点数位数？

1

spring

class="cursor-pointer"> 详细描述

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本地连接阿里云mysql运行任务，mysql经常会断开，需要重新再获取一次请求

1

数据库

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

        <!-- c3p0连接池的私有属性 -->
        <property name="maxPoolSize" value="30"/>
        <property name="minPoolSize" value="10"/>
        <!-- 关闭连接后不自动commit -->
        <property name="autoCommitOnClose" value="false"/>
        <!-- 获取连接超时时间 -->
        <property name="checkoutTimeout" value="60000"/>
        <!-- 当获取连接失败重试次数 -->
        <property name="acquireRetryAttempts" value="2"/>

### Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 21,301,201 milliseconds ago.  The last packet sent successfully to the server was 18,933 milliseconds ago.
; SQL []; Communications link failure

The last packet successfully received from the server was 21,301,201 milliseconds ago.  The last packet sent successfully to the server was 18,933 milliseconds ago.; nested exception is com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 21,301,201 milliseconds ago.  The last packet sent successfully to the server was 18,933 milliseconds ago.
	at org.springframework.jdbc.support.SQLExceptionSubclassTranslator.doTranslate(SQLExceptionSubclassTranslator.java:99)
	at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:73)
	at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:81)
	at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:73)
	at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:446)
	at com.sun.proxy.$Proxy13.selectList(Unknown Source)
	at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:230)
	at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:119)
	at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:63)
	at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:52)
	at com.sun.proxy.$Proxy14.queryAllPaper(Unknown Source)
	at service.impl.PaperServiceImpl.queryAllPaper(PaperServiceImpl.java:50)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
	at org.springframework.remoting.support.RemoteInvocationTraceInterceptor.invoke(RemoteInvocationTraceInterceptor.java:78)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
	at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
	at com.sun.proxy.$Proxy15.queryAllPaper(Unknown Source)
	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.springframework.remoting.support.RemoteInvocation.invoke(RemoteInvocation.java:212)
	at org.springframework.remoting.support.DefaultRemoteInvocationExecutor.invoke(DefaultRemoteInvocationExecutor.java:39)
	at org.springframework.remoting.support.RemoteInvocationBasedExporter.invoke(RemoteInvocationBasedExporter.java:78)
	at org.springframework.remoting.rmi.RmiBasedExporter.invoke(RmiBasedExporter.java:73)
	at org.springframework.remoting.rmi.RmiInvocationWrapper.invoke(RmiInvocationWrapper.java:74)
	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 sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:357)
	at sun.rmi.transport.Transport$1.run(Transport.java:200)
	at sun.rmi.transport.Transport$1.run(Transport.java:197)
	at java.security.AccessController.doPrivileged(Native Method)
	at sun.rmi.transport.Transport.serviceCall(Transport.java:196)
	at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:573)
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:835)
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:688)
	at java.security.AccessController.doPrivileged(Native Method)
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:687)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 21,301,201 milliseconds ago.  The last packet sent successfully to the server was 18,933 milliseconds ago.
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
	at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
	at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:981)
	at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3465)
	at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3365)
	at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3805)
	at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2478)
	at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2625)
	at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2551)
	at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1861)
	at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1192)
	at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.execute(NewProxyPreparedStatement.java:67)
	at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:59)
	at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:73)
	at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:60)
	at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:267)
	at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:137)
	at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:96)
	at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:77)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:108)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:102)
	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.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:433)
	... 44 more
Caused by: java.net.SocketException: Connection reset
	at java.net.SocketInputStream.read(SocketInputStream.java:210)
	at java.net.SocketInputStream.read(SocketInputStream.java:141)
	at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:100)
	at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:143)
	at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:173)
	at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2954)
	at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3375)
	... 66 more

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