后台常见报错处理和注意问题（一）

1、接口注入问题：

@Controller
@Scope("prototype")
public class GenuineManagementAction extends BaseAction {

    private static final long serialVersionUID = -3797612994929924322L;

    @Resource
    private GenuineManagementService genuineManagementService;
    @Resource//这样写是有问题的，去掉即可正常
    private GenuineManagement genuineManagement;

}

  @Resource代表注入，只有接口才能注入，而GenuineManagement 是一个实体类，所以加上@Resource 会报如下错误：

Unable to instantiate Action, genuineManagementAction, 

No matching bean of type [com.vrv.paw.domain.GenuineManagement] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency.

Unable to instantiate Action, genuineManagementAction,  defined for 'genuineManagementAction_listUI' in namespace '/'Error creating bean with name 'genuineManagementAction': Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.vrv.paw.domain.GenuineManagement] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@javax.annotation.Resource(mappedName=, shareable=true, description=, name=, type=class java.lang.Object, authenticationType=CONTAINER, lookup=)} - action - file:/E:/workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp4/wtpwebapps/JJFX/WEB-INF/classes/struts-extend.xml:420:89
    at com.opensymphony.xwork2.DefaultActionInvocation.createAction(DefaultActionInvocation.java:318)

2、org.springframework.dao.InvalidDataAccessApiUsageException: The given object has a null identifier: com.paixie.domain.Users;

出现这个异常，一般来说主要修改时候主键没有传递或者name属性指定错误。

解决方案：你要把你的更新的实例的主键传过去，可以以hidden的方式传。

<!-- ID -->
<input id="id" type="hidden" name="controlMeasures.id" value="<s:property value='controlMeasures.id'/>">

3、service层的dao指向一定要正确，否则会出现问题，如果指向的是别的dao，那么在调用查询方法的时候，查询的表就是别的表了。

一方面是@Resource(name="controlMeasuresDao")，这个指向要正确

另一方面下面这种指向也是有问题的，指向的是BaseDao，而我们应该是要指向ControlMeasuresDao

@Service("controlMeasuresService")
@Transactional
public class ControlMeasuresServiceImpl extends BaseServiceImpl<ControlMeasures> implements ControlMeasuresService {

    protected BaseDao<ControlMeasures> controlMeasuresDao;
    public BaseDao<ControlMeasures> getControlMeasuresDao() {
        return controlMeasuresDao;
    }
    @Resource(name="controlMeasuresDao")
    public void setControlMeasuresDao (BaseDao<ControlMeasures> controlMeasuresDao) {
        this.controlMeasuresDao = controlMeasuresDao;
        this.baseDao = controlMeasuresDao;
    }
    @Override
    public ControlMeasures queryByConId(Integer id) {
        return baseDao.queryById(id);
    }
}

需要修改一下，要向下面这样修改，才会指向的是ControlMeasuresDao

public class ControlMeasuresServiceImpl extends BaseServiceImpl<ControlMeasures> implements ControlMeasuresService {
    protected ControlMeasuresDao controlMeasuresDao;
    @Resource(name="controlMeasuresDao")
    public void setGenuineManagementDao(ControlMeasuresDao controlMeasuresDao) {
        this.controlMeasuresDao = controlMeasuresDao;
        this.baseDao = controlMeasuresDao;
    }
    @Override
    public void deleteGmId(Integer id) {
        controlMeasuresDao.deleteGmId(id);
        //如果指向不对的话，那么在这里这个deleteGmId就会提示你要在BaseDao里面去新建，而实际上我们是要在ControlMeasuresDao里面去建
    }
}

　　如果指向不对的话，那么在这里这个deleteGmId就会提示你要在BaseDao里面去新建，而实际上我们是要在ControlMeasuresDao里面去建

4、修改数据的时候，调用edit方法一定要传个id过去

//修改规则库管理
        function editControl(){
            var selectRows = $("#ruleManagementTable").datagrid('getSelections');
            if(selectRows.length > 1){
                showMsg("只能选择一个修改!");
                return false;
            }
            showWindow("修改规则库管理","genuineManagementAction_editUI.do?controlMeasures.id="+selectRows[0].id,"500","380",true);
        }

如果不传id，那么下面是获取不到那个实体类的

//修改规则库UI
    public String editUI(){
        if(controlMeasures != null){
            controlMeasures = controlMeasuresService.queryById(controlMeasures.getId());
        }
        return RETURN_EDITUI;
    }

5、两页面之间传值：

（1）首先做为参数传给后台

    function addControl(){
        var policyName = $("#strategyName").val();
        showWindow("新建规则库管理","genuineManagementAction_addUI.do?genuineManagement.policyName="+policyName,"500","380",true);
    }

（2）其次在addUI方法上把值set进去

    public String addUI(){
        if(genuineManagement.getPolicyName() != null && !"".equals(genuineManagement.getPolicyName())){
            getRequest().setAttribute("policyName", genuineManagement.getPolicyName());
        }
        return RETURN_ADDUI;
    }

（3）在此在addUI页面上把值获取，并赋予form表单里的隐藏域。

var policyName = '<s:property value="genuineManagement.policyName"></s:property>';
$("#policyName").val(policyName);

<form id="controlMeasures_add">
    <input type="hidden" id="policyName" name="controlMeasures.policyName"

注意：获取的时候是原实体的属性，传值的时候是目标实体的属性，如上面标红初。

这样在获取controlMeasures实体的时候，就可以获取到传过来的policyName了

6、使用form表单提交的时候，form表单自动会提交各参数，如果url路径后面加了参数，那么会先复制url的参数，然后form表单里默认的参数，会覆盖url路径后面的参数

$("#buttonSubmit").click(function(){
            debugger
            var softDisplayName = $("#softDisplayName").val();
            var softId = $("#softDisplayName option[value='" + softDisplayName + "']").attr("softId");
            var version = $("#version").val(),
                type = $("#type").val(),
                serialNumber = $("#serialNumber").val();
            $("#genuineSerialNumberManagementAction_add").form("submit",{
                method : "POST",
                url : "genuineSerialNumberManagementAction_add.do?disc=genuineSerialNumberManagement_add&genuineSerialNumberManagement.softDisplayName="
                        + escape(escape(softDisplayName)) + "&genuineSerialNumberManagement.version=" + escape(escape(version))
                        + "&genuineSerialNumberManagement.serialNumber=" + escape(escape(serialNumber))
                        + "&genuineSerialNumberManagement.type=" + type
                        + "&genuineSerialNumberManagement.softId=" + softId,
                timeout : 3000000,
                success : 

如上面问题，如果form表单里面没给$("#softId")赋值，那么form表单默认的softId参数就是空的，那么传到后台就始终获取不到softId的值，需要修改下：

$("#buttonSubmit").click(function(){
            var softDisplayName = $("#softDisplayName").val();
            var softId = $("#softDisplayName option[value='" + softDisplayName + "']").attr("softId");
            $("#softId").val(softId);
            $("#genuineSerialNumberManagementAction_add").form("submit",{
                method : "POST",
                url : "genuineSerialNumberManagementAction_add.do",
                timeout : 3000000,
                success :

这样既可获取到，记住：提交采用form形式无需加url参数。

7、为防止点击页面出现404错误，需要在  struts-extend.xml  文件上加上下面配置：

<!-- 正版化统计 -->
        <action name="genuineManagementStaticAction_*" class="genuineManagementStaticAction" method="{1}">
            <result name="{1}">/WEB-INF/pages/genuineManagementStaticAction/{1}.jsp</result>
            <result name="toList" type="redirectAction">/genuineManagementStaticAction_listUI.do</result>
        </action>

8、org.hibernate.hql.ast.QuerySyntaxException: unexpected AST node: .  异常处理方法

public void list() {
        try {
            HQLBuilderUtil hql = new HQLBuilderUtil(Software.class);
            if(software!=null && software.getSoftId()!=null && !"".equals(software.getSoftId())){
                Integer softId = software.getSoftId();
                hql.addWhereClause(" this.softId=? ", softId);
            }
            Integer pcCount = pcInfoService.queryAll().size();//PC总数
            GridData<Software> reportlogs = softwareService.getPageView(hql, getPageNum(), getPageSize());
            List<Software> list = reportlogs.getRows();
            for (int i = 0; i < list.size(); i++) {
                //取安装数
                Integer installCount = genuineManagementStaticService.queryInstallNum(list.get(i).getSoftId());
                NumberFormat numberFormat = NumberFormat.getInstance();
                // 设置精确到小数点后2位
                numberFormat.setMaximumFractionDigits(2);
                String result = numberFormat.format((float) installCount / (float) pcCount * 100) + "%";
                list.get(i).setInstallNum(installCount);
                list.get(i).setInstallPersent(result);
                //取正版数
                Integer genuine = 1;
                Integer genuineCount = genuineManagementStaticService.queryGenuineNum(genuine, list.get(i).getSoftId());
                Integer softCount = genuineManagementStaticService.querySoftNum(list.get(i).getSoftId());
                NumberFormat numberFormatGenuine = NumberFormat.getInstance();
                // 设置精确到小数点后2位
                numberFormat.setMaximumFractionDigits(2);
                String genuineResult = numberFormatGenuine.format((float) genuineCount / (float) softCount * 100) + "%";
                list.get(i).setGenuineNum(genuineCount);
                list.get(i).setGenuinePersent(genuineResult);
                //取最新版本
                GenuineManagementStatic gms = genuineManagementStaticService.queryNewVersion(list.get(i).getSoftId());
                list.get(i).setVersion(gms.getVersion());
            }
            print(ActionUtil.jsonObj(reportlogs));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

 当上面 hql.addWhereClause(" this.softId=? ", softId);  如果没有 =？ 会报错误：

1147240 [http-bio-8080-exec-4] ERROR org.hibernate.hql.PARSER - <AST>:1:55: unexpected AST node: .
org.hibernate.hql.ast.QuerySyntaxException: unexpected AST node: . near line 1, column 55 [  FROM com.vrv.paw.domain.Software this    WHERE  this.softId  ]
    at org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:54)

解决方法：加上 =？ 来与参数对应

9、数据库执行的一个小问题，如果没有executeUpdate()只是设置了执行语句，并没有执行，所以发现删除不了数据库的内容，其实是这个小问题的影响

同时createSQLQuery的执行方法还不一样，如果是createSQLQuery就会报错。

@Override
    public void deleteGmId(Integer gmId) {
        this.getSession().createQuery(" DELETE FROM " + this.clazz.getName() + " WHERE gmId =(:gmId)")
        .setParameter("gmId", gmId)
        .executeUpdate();
    }

10、quote symbol expected 异常处理

严重: Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: /show.jsp(87,33) quote symbol expected

org.apache.jasper.JasperException: /show.jsp(87,33) quote symbol expected这一行表明 ： show.jsp 的87行33列少了一个 引号，行数可能有偏差，我的偏差了一行，实际是 88行少了一个引号～把引号加上就 OK啦，特别是使用struts标签的时候，要特别注意。