jdbc - À propos de l'erreur: java.sql.SQLException: ResultSet.next non appelé

Question

1.` public Res évalueCourse (@FormParam("stuId") int stuId, @FormParam("score") String score) {

        Res res = new Res();
        Connection con = null;
        ResultSet rs = null;
        String[] temp =  score.split(",");
        int count = 0;
        try{
            con = getConnection();
            Statement sm = con.createStatement();
            String selectStuId = "select evaluateId from evaluate where stuId = " + stuId;
            rs = sm.executeQuery(selectStuId);

            for(String s: temp) {
                int scoreInt = Integer.parseInt(s);
                count++;
                switch (count) {
                    case 1:
                        int TEACHPROGRAM = scoreInt;
                        System.out.println("TEACHPROGRAM = " + TEACHPROGRAM);
                        String insert1 = "insert into evaluateDesc(EVALUATEID,ATTRNAME,ATTRSCORE) values(" + rs.getInt("evaluateId")
                                + "," + TEACHPROGRAM + ")";
                        System.out.println(insert1);
                        rs = sm.executeQuery(insert1);
                        if(rs.next()){
                            System.out.println("TEACHPROGRAM = " + rs.getInt(TEACHPROGRAM));
                        }
                        continue;
                    case 2:
                        int LECTURECONTENT = scoreInt;
                        System.out.println("LECTURECONTENT = " + LECTURECONTENT);
                        String insert2 = "insert into evaluateDesc(evaluateId,attrName,attrScore) values (" + rs.getInt("evaluate")
                                + "," + LECTURECONTENT + ")";
                        rs = sm.executeQuery(insert2);
                        if(rs.next()){
                            System.out.println("LECTURECONTENT = " + rs.getInt(LECTURECONTENT));
                        }
                        continue;
                    case 3:
                        int LECTUREMETHOD = scoreInt;
                        System.out.println("LECTUREMETHOD = " + LECTUREMETHOD);
                        String insert3 = "insert into evaluateDesc(evaluateId,attrName,attrScore) values (" + rs.getInt("evaluate")
                                + "," + LECTUREMETHOD + ")";
                        rs = sm.executeQuery(insert3);
                        if(rs.next()){
                            System.out.println("LECTUREMETHOD = " + rs.getInt(LECTUREMETHOD));
                        }
                        continue;
                    case 4:
                        int TSINTERACTION = scoreInt;
                        System.out.println("TSINTERACTION = " + TSINTERACTION);
                        String insert4 = "insert into evaluateDesc(evaluateId,attrName,attrScore) values (" + rs.getInt("evaluate")
                                + "," + TSINTERACTION + ")";
                        rs = sm.executeQuery(insert4);
                        if(rs.next()){
                            System.out.println("TSINTERACTION = " + rs.getInt(TSINTERACTION));
                        }
                        continue;
                    case 5:
                        int EVAMETHOD = scoreInt;
                        System.out.println("EVAMETHOD = " + EVAMETHOD);
                        String insert5 = "insert into evaluateDesc(evaluateId,attrName,attrScore) values (" + rs.getInt("evaluate")
                                + "," + EVAMETHOD + ")";
                        rs = sm.executeQuery(insert5);
                        if(rs.next()){
                            System.out.println("EVAMETHOD = " + rs.getInt(EVAMETHOD));
                        }
                        continue;
                    case 6:
                        int EVALUATE = scoreInt;
                        System.out.println("EVALUATE = " + EVALUATE);
                        String insert6 = "insert into evaluateDesc(evaluateId,attrName,attrScore) values (" + rs.getInt("evaluate")
                                + "," + EVALUATE + ")";
                        rs = sm.executeQuery(insert6);
                        if(rs.next()){
                            System.out.println("EVALUATE = " + rs.getInt(EVALUATE));
                        }
                        break;
                }
            }
        }catch (Exception e){
            e.printStackTrace();
        }

        res.setMsg("评教成功");
        return res;
    }
   `
   

2. Code d'essai :

    void testEvaluateCourse() {
        CourseEvaluateServiceImpl ce = new CourseEvaluateServiceImpl();
        String str = "15,15,10,0,0,0";
        ce.evaluateCourse(1,str.toString());
    }

3. Message d'erreur :

开始尝试连接数据库！
连接成功
TEACHPROGRAM = 15

java.sql.SQLException: 未调用 ResultSet.next
    at oracle.jdbc.driver.GeneratedScrollableResultSet.getInt(GeneratedScrollableResultSet.java:565)
    at oracle.jdbc.driver.GeneratedResultSet.getInt(GeneratedResultSet.java:1350)
    at serviceImpl.CourseEvaluateServiceImpl.evaluateCourse(CourseEvaluateServiceImpl.java:45)
    at service.CourseEvaluateService$evaluateCourse.call(Unknown Source)
    at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:48)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:113)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:133)
    at serviceImpl.CourseEvaluateServiceImplTest.testEvaluateCourse(CourseEvaluateServiceImplTest.groovy:10)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at junit.framework.TestCase.runTest(TestCase.java:154)
    at junit.framework.TestCase.runBare(TestCase.java:127)
    at junit.framework.TestResult.protect(TestResult.java:106)
    at junit.framework.TestResult.runProtected(TestResult.java:124)
    at junit.framework.TestResult.run(TestResult.java:109)
    at junit.framework.TestCase.run(TestCase.java:118)
    at junit.textui.TestRunner.doRun(TestRunner.java:116)
    at com.intellij.junit3.JUnit3IdeaTestRunner.doRun(JUnit3IdeaTestRunner.java:113)
    at junit.textui.TestRunner.doRun(TestRunner.java:109)
    at com.intellij.junit3.JUnit3IdeaTestRunner.startRunnerWithArgs(JUnit3IdeaTestRunner.java:45)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:51)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:237)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
    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:497)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)

Après avoir appelé ResultSet.next(), le curseur passe à la ligne suivante. Et si vous l'appeliez plusieurs fois comme ceci ?
J'ai vraiment vérifié beaucoup d'informations. J'espère que Dieu sera miséricordieux. Je ne suis vraiment qu'un novice avec une compréhension très faible.
Si je pouvais vraiment trouver des informations pour résoudre le problème, je ne viendrais pas ici pour demander ! ! ! !

Answer 1

Prenons le cas 1 comme exemple

rs = sm.executeQuery(selectStuId);

//执行下面的rs.getInt("evaluateId")，之前没有调用过next，会出错
String insert1 = "insert into evaluateDesc(EVALUATEID,ATTRNAME,ATTRSCORE) values(" + rs.getInt("evaluateId")+ "," + TEACHPROGRAM + ")";

rs = sm.executeQuery(insert1);
//这是对的
if(rs.next()){
    System.out.println("TEACHPROGRAM = " + rs.getInt(TEACHPROGRAM));
}