package com.hy.filter;

import java.io.IOException;

import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;

import javax.servlet.annotation.WebFilter;

import javax.servlet.annotation.WebInitParam;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.hy.utils.StringUtil;

@WebFilter(urlPatterns = { "*.do" },

initParams = {

@WebInitParam(name = "encoding", value = "UTF-8")

})

public class CharacterEncodingFilter implements Filter {

private String encoding = "UTF-8";

@Override

public void init(FilterConfig filterConfig) throws ServletException {

String encoding = filterConfig.getInitParameter("encoding");

System.out.println("encoding="+encoding);

if(StringUtil.isNotEmpty(encoding)) {

this.encoding = encoding;

}

}

@Override

public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain)

throws IOException, ServletException {

HttpServletRequest request = (HttpServletRequest) req;

HttpServletResponse response = (HttpServletResponse) resp;

request.setCharacterEncoding(encoding);

response.setCharacterEncoding(encoding);

response.setContentType("text/html;charset="+encoding);

chain.doFilter(request, response);

return;

}

@Override

public void destroy() {

}

}

create table worker(

       wid int primary key,

       wname varchar2(20),

       age int       

)

select * from user_tables;

select * from user_col_comments where table_name = 'WORKER'

select * from worker;

insert into worker values(1,'fbb',10);

commit;

rollback;

##Oracle 自动开启事务，但是需要手动的 提交事务或回滚事务

## mysql 默认自动开启事务，自动提交事务，失败自动回滚