问题遇到的现象和发生背景
在学习黑马旅游网的代码时，加上一行代码就会报错，而去掉就正常
package cn.itcast.travel.web.servlet;
import cn.itcast.travel.domain.PageBean;
import cn.itcast.travel.domain.Route;
import cn.itcast.travel.service.impl.RouteService;
import cn.itcast.travel.service.impl.RouteServiceImpl;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
@WebServlet("/route/*")
public class RouteServlet extends BaseServlet {
private RouteService routeService = new RouteServiceImpl();
/**
* 分页查询
* @param request
* @param response
* @throws ServletException
* @throws IOException
*/
public void pageQuery(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1.接受参数
String currentPageStr = request.getParameter("currentPage");
String pageSizeStr = request.getParameter("pageSize");
String cidStr = request.getParameter("cid");
//接受rname 线路名称
String rname = request.getParameter("rname");
rname = new String(rname.getBytes("iso-8859-1"),"utf-8");
int cid = 0;//类别id
//2.处理参数
if(cidStr != null && cidStr.length() > 0 && !"null".equals(cidStr)){
cid = Integer.parseInt(cidStr);
}
int currentPage = 0;//当前页码，如果不传递，则默认为第一页
if(currentPageStr != null && currentPageStr.length() > 0){
currentPage = Integer.parseInt(currentPageStr);
}else{
currentPage = 1;
}
int pageSize = 0;//每页显示条数，如果不传递，默认每页显示5条记录
if(pageSizeStr != null && pageSizeStr.length() > 0){
pageSize = Integer.parseInt(pageSizeStr);
}else{
pageSize = 5;
}
//3. 调用service查询PageBean对象
PageBean<Route> pb = routeService.pageQuery(cid, currentPage, pageSize,rname);
//4. 将pageBean对象序列化为json，返回
writeValue(pb,response);
}
}
问题相关代码，请勿粘贴截图
rname = new String(rname.getBytes("iso-8859-1"),"utf-8");
只要加上这行，就会报错
运行结果及报错内容
java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at cn.itcast.travel.web.servlet.BaseServlet.service(BaseServlet.java:36)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at cn.itcast.travel.web.filter.CharchaterFilter.doFilter(CharchaterFilter.java:32)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
at java.base/java.lang.Thread.run(Thread.java:844)
