com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Duplicate entry '1' for key 'PRIMARY'
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
at com.mysql.jdbc.Util.getInstance(Util.java:387)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:932)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3878)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3814)
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.executeUpdateInternal(PreparedStatement.java:2073)
at com.mysql.jdbc.PreparedStatement.executeUpdateInternal(PreparedStatement.java:2009)
at com.mysql.jdbc.PreparedStatement.executeLargeUpdate(PreparedStatement.java:5094)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1994)
at org.dao.LoginDao.addInfo(LoginDao.java:73)
at org.servlet.LeaveMessageServlet.doGet(LeaveMessageServlet.java:39)
at org.servlet.LeaveMessageServlet.doPost(LeaveMessageServlet.java:44)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:528)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1099)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:670)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2508)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2497)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
create table messagess(id int not null unique auto_increment,name varchar(20) default null ,time Date default null,title varchar(50) default null,message varchar(500) default null ,primary key(id))ENGINE=MyISAM DEFAULT CHARSET=GBK AUTO_INCREMENT=1 ;
create table loginss(id int not null auto_increment,name varchar(20) default null ,password varchar(50) default null,primary key (id))ENGINE=MyISAM DEFAULT CHARSET=GBK AUTO_INCREMENT=1 ;
主键冲突，有可能是同一数据多次插入了。插入数据时带上ignore。
1L正解，检查下该表的字段是不是有多个主键
select * from table where x= PRIMARY,然后删除或修改重复的条目。
主键数据重复
看这个帖子，帮你问了下朋友
http://www.yl1001.com/group_article/5461468980778720.htm?classic_id=4941468982929372#comment_4941468982929372
这里只有你的建表语句，并没有你的插入数据语句，所以只能推断你的场景了。
messagess表的主键是id，loginss的主键也是id；两个表的id都是自增的，这样的话插入的时候就不要给id赋值，跳过他会自动赋值。
报错的原因：表中已经有id为1的记录，你继续往里插新记录了，但是id还是1.
解决方法：插入数据跳过id，或者用insert ingore（已有记录不插入新记录）
报错已经很明显了，主键冲突问题，插入数据时确保主键的唯一性就行了~