本文介绍了状态更新不起作用的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
当我单击说出"(p:commandButton)提交状态时，出现以下异常.该异常是由行的commentList()函数引起的
When I am clicking the Speak Out(p:commandButton) to submit a status, I am getting the following exception. The exception is caused by commentList() function by the line
Query query = em.createQuery(
"SELECT c FROM Comment c WHERE c.statusId=" + statusId,
Comment.class);
1)Home.xhtml
1)Home.xhtml
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:p="http://primefaces.org/ui"
xmlns:c="http://java.sun.com/jsp/jstl/core">
<h:head>
</h:head>
<div style="width: 100%; background-color: #EEEEEE;">
<h:panelGrid columns="1">
<h:form id="speakout">
<h:outputText value="Speak Out" />
<br />
<h:outputText value="Share whats in your mind.!"
style="color:#aaaaaa;font-size:x-small;" />
<p:inputTextarea name="content" id="sharetext" cols="60" rows="2"
onclick="this.value='';" value="#{statusBean.status.statusmsg}"
style="text-size:small;" />
<br />
<p:commandButton type="submit" value="Speak Out"
action="#{statusBean.save}" ajax="false"
styleClass="buttonstyle" />
<br />
</h:form>
</div>
<!-- -->
<div class="items">
<h:form>
<ui:repeat var="p" value="#{statusBean.statusList}">
<ui:fragment rendered="#{p.statusmsg!=null}">
<div class="status">
<!-- for text status msg check-->
<h:commandLink action="#{friendBean.gotoFriendProfile(p.email)}"
styleClass="link">
<img src="../images/profilePicture/thumb/#{p.picture}"
style="height: 39px; width: 39px;" />
<h:outputText value="#{p.statusBy}:" />
</h:commandLink>
<h:outputText value="#{p.statusmsg}" styleClass="textstyle1" />
<h:outputText value="#{p.timeMillis}"
style="font-size:xx-small;float:right;color:#bbbbbb;font-style: italic;">
<f:converter converterId="timeConverter" />
</h:outputText>
<h:commandLink action="#{statusBean.deleteStatus(p.statusId)}"
value="Delete"></h:commandLink>
<p:growl />
<br />
<ui:repeat var="q" value="#{statusBean.commentList(p.statusId)}" >
<div class="barcomment">
<br />
<h:commandLink action="#{friendBean.gotoFriendProfile(q.email)}"
styleClass="link">
<img src="../images/profilePicture/thumb/#{q.picture}"
style="height: 29px; width: 29px;" />
<h:outputText value="#{q.commentBy}:" />
</h:commandLink>
<h:outputText value=" #{q.comment}" styleClass="textstyle1" />
<h:outputText value="#{q.timeMillis}"
style="font-size:xx-small;float:right;font-style: italic;">
<f:converter converterId="timeConverter" />
</h:outputText>
<h:commandLink action="#{statusBean.deleteComment(q.commentId)}"
value="Delete"></h:commandLink>
</div>
</ui:repeat>
<br />
<div class="comment">
<p:inputText value="#{statusBean.comment.comment}"
styleClass="box" />
<p:commandLink value="Views"
action="#{statusBean.update(p.statusId)}"
ajax="false" styleClass="link" />
</div>
<br />
</div>
</ui:fragment>
</ui:repeat>
</h:form>
</div>
</h:body>
</html>
2)状态Bean
package com.bean;
public class StatusBean {
Date d;
Comment comment;
Status status;
private EntityManager em;
private UploadedFile uploadedFile;
public Comment getComment() {
return comment;
}
public void setComment(Comment comment) {
this.comment = comment;
}
public Status getStatus() {
return status;
}
public void setStatus(Status status) {
this.status = status;
}
public StatusBean() {
d = new Date();
comment = new Comment();
status = new Status();
EntityManagerFactory emf = Persistence
.createEntityManagerFactory("FreeBird");
em = emf.createEntityManager();
}
public List<Status> getStatusList() {
FacesContext context = FacesContext.getCurrentInstance();
HttpSession session = (HttpSession) context.getExternalContext()
.getSession(true);
User user = (User) session.getAttribute("userdet");
Query query = em.createQuery("SELECT s FROM Status s WHERE s.email='"
+ user.getEmail() + "' ORDER BY s.timeMillis desc",
Status.class);
List<Status> results = query.getResultList();
Query query1 = em.createQuery("SELECT f FROM Friend f WHERE f.email='"
+ user.getEmail() + "'", Friend.class);
List<Friend> results1 = query1.getResultList();
Iterator<Friend> it = results1.listIterator();
while (it.hasNext()) {
String email = it.next().getFriendEmail();
Query query2 = em.createQuery(
"SELECT s FROM Status s WHERE s.email='" + email
+ "' ORDER BY s.timeMillis desc", Status.class);
List<Status> results2 = query2.getResultList();
results.addAll(results2);
}
Collections.sort(results);
int index = 0;
int end = index+5 > results.size() ? results.size() : index+5;
List<Status> subList = results.subList(0, end);
session.setAttribute("statusindex", end);
return subList;
}
public String save() {
FacesContext context = FacesContext.getCurrentInstance();
HttpSession session = (HttpSession) context.getExternalContext()
.getSession(false);
User user = (User) session.getAttribute("userdet");
status.setEmail(user.getEmail());
status.setStatusBy(user.getFirstName());
d = new Date();
status.setTimeMillis(d.getTime());
status.setPicture(user.getImage());
System.out.println("status save called");
em.getTransaction().begin();
em.persist(status);
em.getTransaction().commit();
FacesContext context2 = FacesContext.getCurrentInstance();
context2.getExternalContext().getSessionMap().remove("statusBean");
return "success";
}
public String update(String statusId) {
System.out.println("Update Called...");
FacesContext context = FacesContext.getCurrentInstance();
HttpSession session = (HttpSession) context.getExternalContext()
.getSession(true);
User user = (User) session.getAttribute("userdet");
comment.setStatusId(Integer.parseInt(statusId));
comment.setCommentBy(user.getFirstName());
comment.setPicture(user.getImage());
comment.setEmail(user.getEmail());
d = new Date();
comment.setTimeMillis(d.getTime());
em.getTransaction().begin();
em.persist(comment);
em.getTransaction().commit();
getComment().setComment("");
FacesContext context2 = FacesContext.getCurrentInstance();
context2.getExternalContext().getSessionMap().remove("statusBean");
return "success";
}
public List<Comment> commentList(String statusId) {
FacesContext context = FacesContext.getCurrentInstance();
Query query = em.createQuery(
"SELECT c FROM Comment c WHERE c.statusId=" + statusId,
Comment.class);
List<Comment> results = query.getResultList();
return results;
}
public String deleteStatus(String statusId) {
Status status = em.find(Status.class, Integer.parseInt(statusId));
FacesContext context = FacesContext.getCurrentInstance();
HttpSession session = (HttpSession) context.getExternalContext()
.getSession(true);
User user = (User) session.getAttribute("userdet");
if (user.getEmail().equals(status.getEmail())) {
em.getTransaction().begin();
em.remove(status);
em.getTransaction().commit();
} else {
context.addMessage(null, new FacesMessage(
"You don't have permission to delete"));
}
return "success";
}
public String deleteComment(String commentId) {
Comment comment = em.find(Comment.class, Integer.parseInt(commentId));
FacesContext context = FacesContext.getCurrentInstance();
HttpSession session = (HttpSession) context.getExternalContext()
.getSession(true);
User user = (User) session.getAttribute("userdet");
Status status = em.find(Status.class, comment.getStatusId());
if (user.getEmail().equals(status.getEmail())
|| comment.getEmail().equals(user.getEmail()))
{
em.getTransaction().begin();
em.remove(comment);
em.getTransaction().commit();
} else {
context.addMessage(null, new FacesMessage(
"You don't have permission to delete"));
}
return "success";
}
}
3)异常
Mar 03, 2013 9:10:26 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [Faces Servlet] in context with path [/FreeBird_v.6] threw exception [An exception occurred while creating a query in EntityManager:
Exception Description: Syntax error parsing the query [SELECT c FROM Comment c WHERE c.statusId=], line 0, column -1: unexpected end of query.
Internal Exception: NoViableAltException(-1@[792:1: comparisonExpressionRightOperand returns [Object node] : (n= arithmeticExpression | n= nonArithmeticScalarExpression | n= anyOrAllExpression );])] with root cause
NoViableAltException(-1@[792:1: comparisonExpressionRightOperand returns [Object node] : (n= arithmeticExpression | n= nonArithmeticScalarExpression | n= anyOrAllExpression );])
at org.eclipse.persistence.internal.libraries.antlr.runtime.DFA.noViableAlt(DFA.java:159)
at org.eclipse.persistence.internal.libraries.antlr.runtime.DFA.predict(DFA.java:144)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.comparisonExpressionRightOperand(JPQLParser.java:4326)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.comparisonExpression(JPQLParser.java:4215)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.simpleConditionalExpressionRemainder(JPQLParser.java:3389)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.simpleConditionalExpression(JPQLParser.java:3326)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.conditionalPrimary(JPQLParser.java:3275)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.conditionalFactor(JPQLParser.java:3194)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.conditionalTerm(JPQLParser.java:3103)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.conditionalExpression(JPQLParser.java:3029)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.whereClause(JPQLParser.java:2986)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.selectStatement(JPQLParser.java:380)
at org.eclipse.persistence.internal.jpa.parsing.jpql.antlr.JPQLParser.document(JPQLParser.java:281)
at org.eclipse.persistence.internal.jpa.parsing.jpql.JPQLParser.parse(JPQLParser.java:134)
at org.eclipse.persistence.internal.jpa.parsing.jpql.JPQLParser.buildParseTree(JPQLParser.java:95)
at org.eclipse.persistence.internal.jpa.EJBQueryImpl.buildEJBQLDatabaseQuery(EJBQueryImpl.java:215)
at org.eclipse.persistence.internal.jpa.EJBQueryImpl.buildEJBQLDatabaseQuery(EJBQueryImpl.java:190)
at org.eclipse.persistence.internal.jpa.EJBQueryImpl.<init>(EJBQueryImpl.java:142)
at org.eclipse.persistence.internal.jpa.EJBQueryImpl.<init>(EJBQueryImpl.java:126)
at org.eclipse.persistence.internal.jpa.EntityManagerImpl.createQuery(EntityManagerImpl.java:1475)
at org.eclipse.persistence.internal.jpa.EntityManagerImpl.createQuery(EntityManagerImpl.java:1497)
at com.bean.StatusBean.commentList(StatusBean.java:227)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at javax.el.BeanELResolver.invoke(BeanELResolver.java:484)
at javax.el.CompositeELResolver.invoke(CompositeELResolver.java:161)
at org.apache.el.parser.AstValue.getValue(AstValue.java:159)
at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:189)
at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:106)
at com.sun.faces.facelets.component.UIRepeat.getValue(UIRepeat.java:268)
at com.sun.faces.facelets.component.UIRepeat.getDataModel(UIRepeat.java:244)
at com.sun.faces.facelets.component.UIRepeat.setIndex(UIRepeat.java:434)
at com.sun.faces.facelets.component.UIRepeat.doVisitChildren(UIRepeat.java:642)
at com.sun.faces.facelets.component.UIRepeat.visitTree(UIRepeat.java:600)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1487)
at com.sun.faces.facelets.component.UIRepeat.visitTree(UIRepeat.java:606)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1487)
at javax.faces.component.UIForm.visitTree(UIForm.java:331)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1487)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1487)
at com.sun.faces.lifecycle.RestoreViewPhase.deliverPostRestoreStateEvent(RestoreViewPhase.java:258)
at com.sun.faces.lifecycle.RestoreViewPhase.execute(RestoreViewPhase.java:245)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:97)
at com.sun.faces.lifecycle.RestoreViewPhase.doPhase(RestoreViewPhase.java:107)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:114)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:308)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79)
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:225)
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:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
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:1001)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)
推荐答案
您似乎要传递给commentList(String statusId)的p.statusId是空的.您可以尝试将System.out.println("statusId: "+statusId);放在commentList(String statusId)方法的开头.
It seems like p.statusId which you are passing to commentList(String statusId) is empty. You can try to put System.out.println("statusId: "+statusId); to begining of commentList(String statusId) method.
您也可以将<h:outputText value="p.statusId: #{p.statusId}"/>放在前面:
<ui:repeat var="q" value="#{statusBean.commentList(p.statusId)}" >
我也不确定将statusBean.commentList(p.statusId)放在ui:repeat value属性中是否是一种好习惯.您最终可能比您想要的更多地从数据库检索状态列表.最好将其预加载到某些属性，然后在需要时将其传递.
I'm also not sure if it's good practice to put statusBean.commentList(p.statusId) in ui:repeat value attribute. You can end up retrieving list of Statuses from DB more often than you wanted to. It would be better to preload it to some property and then pass it where required.
更新
也替换:
Query query = em.createQuery(
"SELECT c FROM Comment c WHERE c.statusId=" + statusId, Comment.class);
使用
TypedQuery<Comment> query = em.createQuery(
"SELECT c FROM Comment c WHERE c.statusId = :statusId", Comment.class);
query.setParameter("statusId", statusId);
这样，您的查询就可以更安全地防止SQL注入和语法错误.
This way your queries are safer against SQL injection and syntax errors.
更新2
private class StatusWrapper {
private Status status;
private List<Comment> comments;
}
在您的StatusBean中
In your StatusBean
...
private List<StatusWrapper> statuses;
...
(getters setters)
...
public StatusBean() {
...
initStatuses();
}
...
public void initStatuses() {
statuses=new ArrayList<>();
List<Status> stats=getStatusList();
for(Status status:stats) {
StatusWrapper wrapper=new StatusWrapper();
wraper.setStatus(status);
wraper.setComments(commentList(status.getStatusId()));
statuses.add(wrapper);
}
仅在页面中使用statuss属性.希望很清楚(可能有一些错别字.)
Than in your page just use statuses property. Hope it's clear (there are some typos probably.)
这篇关于状态更新不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！