Question

我想列出所有国家/地区以获取所有相应的州和货币。

ConfFacade.java

public Result<List<Country>> listCountries() {
    try {
        String HQL = "SELECT DISTINCT o FROM Ocountry o LEFT JOIN FETCH o.ostate, o.ocurrency";
        List<Country> list = em.createQuery(HQL).getResultList();

        return new Result(Status.SUCCESS, list);
    } catch(Exception e) {
        e.printStackTrace();
        return new Result<>(Status.ERROR, Exception.GENERAL, e.getMessage());
    }
}

ConfFacadeLocal.java

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public interface ConfFacadeLocal {
    
    public Result<List<Country>> listCountries();
    
}

＆＃13;

这是我使用的 jsp 并对其进行编码：

listCountries.jsp

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<%
        try {
            InitialContext ctx = new InitialContext();
            ConfFacadeLocal confFacadeLocal = (ConfFacadeLocal)ctx.lookup("java:comp/env/tomin");

            Result<List<Country>> result = confFacadeLocal.listCountries();
            if(result.isUnsuccessful()) {
                throw new Exception(result.getErrMsg());
            }
            
            List<Country> countryList = result.getObject();
            if(countryList == null) {
                throw new Exception("Error.");
            }
            out.print("OK");
            
    %>
            
            <table border="1" align="center" style="width:50%">
            <thead>
                <tr>
                    <th>country code</th>
                    <th>currency code</th>
                    <th>state id</th>
                    <th>state description</th>
                    
                </tr>
            </thead>
            <tbody><%              
            for (Ocountry country : countryList){ %>
                <tr>
                    <td><%=country.getOccode()%></td>
                    <td><%=country.getOcurrency().getOcucode()%></td>
                    <td><%=country.getOstate().getOsid()%></td>
                    <td><%=country.getOstate().getOsdesc()%></td>

                </tr><%
            }
        } catch (Exception e) {
            e.printStackTrace();
            out.print("Error: " + e.getMessage());
        } %>
        
              
     
            </tbody>
        </table>

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这是我得到的错误：

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cannot find symbol
  symbol:   method getOstate()
  location: variable country of type com.ejb.entities.conf.Country
PWC6197: An error occurred at line: 42 in the jsp file: /country/listCountries.jsp
PWC6199: Generated servlet error:
cannot find symbol
  symbol:   method getOstate()
  location: variable country of type com.ejb.entities.conf.Country
	at org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:129)
	at org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:299)
	at org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:392)
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java:453)
	at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:625)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:375)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:473)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:377)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
	at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
	at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
	at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
	at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
	at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:415)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:282)
	at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:459)
	at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:167)
	at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:201)
	at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:175)
	at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235)
	at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
	at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284)
	at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201)
	at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133)
	at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112)
	at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
	at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:561)
	at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112)
	at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117)
	at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56)
	at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137)
	at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:565)
	at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:545)
	at java.lang.Thread.run(Thread.java:745)

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任何人都可以帮忙修复它吗？

Answer 1

从您的 JSP 错误日志中，我猜您错过了向#listCountries bean接口声明ConfFacadeLocal方法。

向界面添加所需的方法声明应该可以解决问题：

public interface ConfFacadeLocal {

  // other API methods ...

  public Result<List<Country>> listCountries();

}

Answer 2

那里（第41行）：

 <td><%=currency.getOcucode()%></td>

您正在使用尚未声明的货币变量。

看来货币是你程序中'Country'类的一个属性，所以也许你应该写一下

 <td><%=country.getCurrency().getOcucode()%></td>

'state'变量存在同样的问题。

HQL - 列出国家/地区并获取所有州和货币

2 个答案: