我是新手，对Eng不好 现在我有问题当我在这里插入新行时返回null是错误。
INFO: javax.el.PropertyNotFoundException: /index.xhtml @143,70 value="#{studentCtrl.student.teacher.teachId}": Target Unreachable, 'teacher' returned null
javax.el.PropertyNotFoundException: /index.xhtml @143,70 value="#{studentCtrl.student.teacher.teachId}": Target Unreachable, 'teacher' returned null
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:100)
at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getConvertedValue(HtmlBasicInputRenderer.java:95)
at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectOneValue(MenuRenderer.java:201)
at com.sun.faces.renderkit.html_basic.MenuRenderer.getConvertedValue(MenuRenderer.java:318)
at javax.faces.component.UIInput.getConvertedValue(UIInput.java:1046)
at javax.faces.component.UIInput.validate(UIInput.java:976)
at javax.faces.component.UIInput.executeValidate(UIInput.java:1249)
at javax.faces.component.UIInput.processValidators(UIInput.java:712)
at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1258)
at javax.faces.component.UIForm.processValidators(UIForm.java:253)
at com.sun.faces.context.PartialViewContextImpl$PhaseAwareVisitCallback.visit(PartialViewContextImpl.java:552)
at com.sun.faces.component.visit.PartialVisitContext.invokeVisitCallback(PartialVisitContext.java:183)
at javax.faces.component.UIForm.visitTree(UIForm.java:381)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1740)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1740)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1740)
at com.sun.faces.context.PartialViewContextImpl.processComponents(PartialViewContextImpl.java:399)
at com.sun.faces.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:263)
at org.primefaces.context.PrimePartialViewContext.processPartial(PrimePartialViewContext.java:60)
at javax.faces.component.UIViewRoot.processValidators(UIViewRoot.java:1193)
at com.sun.faces.lifecycle.ProcessValidationsPhase.execute(ProcessValidationsPhase.java:76)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:198)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:646)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:617)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1521)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1478)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Caused by: javax.el.PropertyNotFoundException: Target Unreachable, 'teacher' returned null
at org.apache.el.parser.AstValue.getTarget(AstValue.java:124)
at org.apache.el.parser.AstValue.getType(AstValue.java:58)
at org.apache.el.ValueExpressionImpl.getType(ValueExpressionImpl.java:168)
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:98)
... 44 more
ส.ค. 19, 2558 3:26:02 หลังเที่ยง com.sun.faces.lifecycle.ProcessValidationsPhase execute
WARNING: javax.el.PropertyNotFoundException: /index.xhtml @143,70 value="#{studentCtrl.student.teacher.teachId}": Target Unreachable, 'teacher' returned null
javax.faces.FacesException: javax.el.PropertyNotFoundException: /index.xhtml @143,70 value="#{studentCtrl.student.teacher.teachId}": Target Unreachable, 'teacher' returned null
at com.sun.faces.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:270)
at org.primefaces.context.PrimePartialViewContext.processPartial(PrimePartialViewContext.java:60)
at javax.faces.component.UIViewRoot.processValidators(UIViewRoot.java:1193)
at com.sun.faces.lifecycle.ProcessValidationsPhase.execute(ProcessValidationsPhase.java:76)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:198)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:646)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:617)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1521)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1478)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Caused by: javax.el.PropertyNotFoundException: /index.xhtml @143,70 value="#{studentCtrl.student.teacher.teachId}": Target Unreachable, 'teacher' returned null
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:100)
at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getConvertedValue(HtmlBasicInputRenderer.java:95)
at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectOneValue(MenuRenderer.java:201)
at com.sun.faces.renderkit.html_basic.MenuRenderer.getConvertedValue(MenuRenderer.java:318)
at javax.faces.component.UIInput.getConvertedValue(UIInput.java:1046)
at javax.faces.component.UIInput.validate(UIInput.java:976)
at javax.faces.component.UIInput.executeValidate(UIInput.java:1249)
at javax.faces.component.UIInput.processValidators(UIInput.java:712)
at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1258)
at javax.faces.component.UIForm.processValidators(UIForm.java:253)
at com.sun.faces.context.PartialViewContextImpl$PhaseAwareVisitCallback.visit(PartialViewContextImpl.java:552)
at com.sun.faces.component.visit.PartialVisitContext.invokeVisitCallback(PartialVisitContext.java:183)
at javax.faces.component.UIForm.visitTree(UIForm.java:381)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1740)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1740)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1740)
at com.sun.faces.context.PartialViewContextImpl.processComponents(PartialViewContextImpl.java:399)
at com.sun.faces.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:263)
... 27 more
Caused by: javax.el.PropertyNotFoundException: Target Unreachable, 'teacher' returned null
at org.apache.el.parser.AstValue.getTarget(AstValue.java:124)
at org.apache.el.parser.AstValue.getType(AstValue.java:58)
at org.apache.el.ValueExpressionImpl.getType(ValueExpressionImpl.java:168)
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:98)
... 44 more
ส.ค. 19, 2558 3:26:02 หลังเที่ยง com.sun.faces.context.AjaxExceptionHandlerImpl handlePartialResponseError
SEVERE: javax.el.PropertyNotFoundException: /index.xhtml @143,70 value="#{studentCtrl.student.teacher.teachId}": Target Unreachable, 'teacher' returned null
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:100)
at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getConvertedValue(HtmlBasicInputRenderer.java:95)
at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectOneValue(MenuRenderer.java:201)
at com.sun.faces.renderkit.html_basic.MenuRenderer.getConvertedValue(MenuRenderer.java:318)
at javax.faces.component.UIInput.getConvertedValue(UIInput.java:1046)
at javax.faces.component.UIInput.validate(UIInput.java:976)
at javax.faces.component.UIInput.executeValidate(UIInput.java:1249)
at javax.faces.component.UIInput.processValidators(UIInput.java:712)
at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1258)
at javax.faces.component.UIForm.processValidators(UIForm.java:253)
at com.sun.faces.context.PartialViewContextImpl$PhaseAwareVisitCallback.visit(PartialViewContextImpl.java:552)
at com.sun.faces.component.visit.PartialVisitContext.invokeVisitCallback(PartialVisitContext.java:183)
at javax.faces.component.UIForm.visitTree(UIForm.java:381)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1740)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1740)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1740)
at com.sun.faces.context.PartialViewContextImpl.processComponents(PartialViewContextImpl.java:399)
at com.sun.faces.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:263)
at org.primefaces.context.PrimePartialViewContext.processPartial(PrimePartialViewContext.java:60)
at javax.faces.component.UIViewRoot.processValidators(UIViewRoot.java:1193)
at com.sun.faces.lifecycle.ProcessValidationsPhase.execute(ProcessValidationsPhase.java:76)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:198)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:646)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:617)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1521)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1478)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Caused by: javax.el.PropertyNotFoundException: Target Unreachable, 'teacher' returned null
at org.apache.el.parser.AstValue.getTarget(AstValue.java:124)
at org.apache.el.parser.AstValue.getType(AstValue.java:58)
at org.apache.el.ValueExpressionImpl.getType(ValueExpressionImpl.java:168)
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:98)
... 44 more
我的学生模特
package model;
// Generated Aug 19, 2015 9:19:39 AM by Hibernate Tools 3.4.0.CR1
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
/**
* Student generated by hbm2java
*/
@Entity
@Table(name = "student", schema = "public")
public class Student implements java.io.Serializable {
private int stuId;
private Teacher teacher;
private String stuName;
private Integer stuAge;
public Student() {
}
public Student(int stuId) {
this.stuId = stuId;
}
public Student(int stuId, Teacher teacher, String stuName, Integer stuAge) {
this.stuId = stuId;
this.teacher = teacher;
this.stuName = stuName;
this.stuAge = stuAge;
}
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "stu_id", unique = true, nullable = false)
public int getStuId() {
return this.stuId;
}
public void setStuId(int stuId) {
this.stuId = stuId;
}
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "stu_teachid")
public Teacher getTeacher() {
return this.teacher;
}
public void setTeacher(Teacher teacher) {
this.teacher = teacher;
}
@Column(name = "stu_name", length = 40)
public String getStuName() {
return this.stuName;
}
public void setStuName(String stuName) {
this.stuName = stuName;
}
@Column(name = "stu_age")
public Integer getStuAge() {
return this.stuAge;
}
public void setStuAge(Integer stuAge) {
this.stuAge = stuAge;
}
}
对于教师模型
package model;
// Generated Aug 19, 2015 9:19:39 AM by Hibernate Tools 3.4.0.CR1
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;
/**
* Teacher generated by hbm2java
*/
@Entity
@Table(name = "teacher", schema = "public")
public class Teacher implements java.io.Serializable {
private int teachId;
private String teachName;
private Set<Student> students = new HashSet<Student>(0);
public Teacher() {
}
public Teacher(int teachId) {
this.teachId = teachId;
}
public Teacher(int teachId, String teachName, Set<Student> students) {
this.teachId = teachId;
this.teachName = teachName;
this.students = students;
}
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name = "teach_id", unique = true, nullable = false)
public int getTeachId() {
return this.teachId;
}
public void setTeachId(int teachId) {
this.teachId = teachId;
}
@Column(name = "teach_name", length = 40)
public String getTeachName() {
return this.teachName;
}
public void setTeachName(String teachName) {
this.teachName = teachName;
}
@OneToMany(fetch = FetchType.LAZY, mappedBy = "teacher")
public Set<Student> getStudents() {
return this.students;
}
public void setStudents(Set<Student> students) {
this.students = students;
}
}
我的道
package dao;
import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.FetchMode;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.criterion.Restrictions;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import model.Student;
import model.Teacher;
@Repository
public class StudentDaoImpl implements StudentDao{
/**
*
*/
private static final long serialVersionUID = 8024106490842552958L;
List<Student> studentList ;
List<Teacher> teacherList ;
@Autowired
SessionFactory sessionFactory ;
@SuppressWarnings("unchecked")
public List<Student> studentList() {
// TODO Auto-generated method stub
Session session = sessionFactory.getCurrentSession() ;
Criteria criteria = session.createCriteria(Student.class , "student") ;
criteria.setFetchMode("student.teacher", FetchMode.JOIN) ;
criteria.createAlias("student.teacher", "teacher") ;
return criteria.list() ;
}
@Override
public boolean delete(Student student) {
try{
sessionFactory.getCurrentSession().delete(student);
return true ;
}catch(Exception e){
return false ;
}
}
@Override
public void studentUpdate(Student student) {
// TODO Auto-generated method stub
sessionFactory.getCurrentSession().saveOrUpdate(student);
}
@Override
public List<Student> studentFind(Student student) {
// TODO Auto-generated method stub
return sessionFactory.getCurrentSession().createCriteria(Student.class)
.add(Restrictions.like("stuName", "%"+student+"%")).list();
}
}
包裹控制器;
import java.util.ArrayList; import java.util.List;
import javax.annotation.PostConstruct;
import model.Student; import model.Teacher;
import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller;
导入service.StudentSer;
@Controller
public class StudentCtrl {
List<Student> studentList ;
List<Student> showStudent ;
List<Student> findShudent ;
Student student ;
Teacher teacher ;
@Autowired
StudentSer studentSer ;
@PostConstruct
public void init(){
student = new Student() ;
studentList = new ArrayList<Student>() ;
showStudent = studentSer.studentList() ;
}
public void save(){
studentSer.studentSave(student);
init();
}
public void update(Student student){
this.student = student ;
studentSer.studentUpdate(student);
init();
}
public void delete(Student student){
studentSer.delete(student) ;
init();
}
public void find(){
studentSer.studentFind(student) ;
}
public List<Student> getStudentList() {
return studentList;
}
public void setStudentList(List<Student> studentList) {
this.studentList = studentList;
}
public List<Student> getShowStudent() {
return showStudent;
}
public void setShowStudent(List<Student> showStudent) {
this.showStudent = showStudent;
}
public Student getStudent() {
return student;
}
public void setStudent(Student student) {
this.student = student;
}
public StudentSer getStudentSer() {
return studentSer;
}
public void setStudentSer(StudentSer studentSer) {
this.studentSer = studentSer;
}
}
这是Xhmtl
<h:form id="addStudent">
<h:panelGrid columns="3" cellpadding="5">
<h:outputLabel for="name" value="Name:" style="font-weight:bold" />
<p:inputText id="name" value="#{studentCtrl.student.stuName}" />
<br />
<h:outputLabel for="name" value="Age:" style="font-weight:bold" />
<p:inputText id="age" value="#{studentCtrl.student.stuAge}" />
<br />
<h:outputLabel for="name" value="Teacher Name:"
style="font-weight:bold" />
<h:selectOneMenu value="#{studentCtrl.student.teacher.teachId}" >
<f:selectItems value="#{teacherCtrl.showTeacher}" var="show"
itemLabel="#{show.teachName}"
itemValue="#{show}" />
</h:selectOneMenu>
<br/>
<p:commandButton value="Save" actionListener="#{studentCtrl.save}"
process="addStudent" update="studbtb" icon="ui-icon-check" />
<p:commandButton value="Clear" type="reset" />
</h:panelGrid>
</h:form>
如何解决问题，Thxq大家^^