java.lang.ExceptionInInitializerError
at cn.itcast.a_one2many.Demo.fun1(Demo.java:17)
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.runners.model.FrameworkMethod1.runReflectiveCall(FrameworkMethod.java:50)atorg.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)atorg.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)atorg.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)atorg.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)atorg.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)atorg.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)atorg.junit.runners.ParentRunner3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner1.schedule(ParentRunner.java:71)atorg.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)atorg.junit.runners.ParentRunner.access000(ParentRunner.java:58)
at org.junit.runners.ParentRunner[Math Processing Error]11.convert(BasicConnectionCreator.java:105)atorg.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.convertSqlException(BasicConnectionCreator.java:123)atorg.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:41)atorg.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58)atorg.hibernate.engine.jdbc.connections.internal.PooledConnections.addConnections(PooledConnections.java:106)atorg.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:40)atorg.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:19)atorg.hibernate.engine.jdbc.connections.internal.PooledConnectionsBuilder.build(PooledConnections.java:138)
at org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.buildPool(DriverManagerConnectionProviderImpl.java:110)
at org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.configure(DriverManagerConnectionProviderImpl.java:74)
at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:217)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:189)
at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.buildJdbcConnectionAccess(JdbcEnvironmentInitiator.java:145)
at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:66)
at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:35)
at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:88)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:234)
... 38 more
Caused by: java.sql.SQLException: Unknown initial character set index '255' received from server. Initial client character set can be forced via the 'characterEncoding' property.
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926)
at com.mysql.jdbc.ConnectionImpl.configureClientCharacterSet(ConnectionImpl.java:1689)
at com.mysql.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:3444)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2062)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:723)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)
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:406)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:302)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282)
at org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:38)
... 53 more
当你排除掉
1,用户名,密码的错误,
2,mysql-connector-java的新老版本的错误
3,数据库方言错误(此处是新版本,注意是MySQL5Dialect)

那么一般是这个错误

强制转换一下就可以了
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