我试图围绕REST服务和杰克逊。我有这个实体：
package de.dpunkt.myaktion.model;
import com.fasterxml.jackson.annotation.JsonIgnore;
import javax.persistence.*;
import javax.validation.constraints.DecimalMin;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import java.util.List;
@NamedQueries({
@NamedQuery(name = Campaign.findByOrganizer, query = "SELECT c FROM Campaign c WHERE c.organizer = :organizer ORDER BY c.name"),
@NamedQuery(name = Campaign.findAll, query = "SELECT a FROM Campaign a ORDER BY a.name"),
@NamedQuery(name = Campaign.getAmountDonatedSoFar, query = "SELECT SUM(d.amount) FROM Donation d WHERE d.campaign = :campaign")
})
@Entity
public class Campaign {
public static final String findByOrganizer = "Campaign.findByOrganizer";
public static final String findAll = "Campaign.findAll";
public static final String getAmountDonatedSoFar = "Campaign.getAmountDonatedSoFar";
@NotNull
@Size(min = 4, max = 30, message = "{campaign.name.size}")
private String name;
@NotNull(message = "{campaign.targetAmount.notNull}")
@DecimalMin(value = "10.00", message = "{campaign.targetAmount.decimalMin}")
private Double targetAmount;
@NotNull(message = "{campaign.donationMinimum.notNull}")
@DecimalMin(value = "1.00", message = "{campaign.donationMinimum.decimalMin}")
private Double donationMinimum;
@Transient
private Double amountDonatedSoFar;
@AttributeOverrides({
@AttributeOverride(name = "name", column = @Column(name = "accountName"))})
@Embedded
private Account account;
@GeneratedValue
@Id
private Long id;
@OneToMany(mappedBy = "campaign", cascade = CascadeType.REMOVE)
@JsonIgnore private List<Donation> donations;
@ManyToOne
@JsonIgnore private Organizer organizer;
public Campaign() {
account = new Account();
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Double getTargetAmount() {
return targetAmount;
}
public void setTargetAmount(Double targetAmount) {
this.targetAmount = targetAmount;
}
public Double getDonationMinimum() {
return donationMinimum;
}
public void setDonationMinimum(Double donationMinimum) {
this.donationMinimum = donationMinimum;
}
public Double getAmountDonatedSoFar() {
return amountDonatedSoFar;
}
public void setAmountDonatedSoFar(Double amountDonatedSoFar) {
this.amountDonatedSoFar = amountDonatedSoFar;
}
public Account getAccount() {
return account;
}
public void setAccount(Account account) {
this.account = account;
}
public void setId(Long id) {
this.id = id;
}
public Long getId() {
return id;
}
public List<Donation> getDonations() {
return donations;
}
public void setDonations(List<Donation> donations) {
this.donations = donations;
}
public Organizer getOrganizer() {
return organizer;
}
public void setOrganizer(Organizer organizer) {
this.organizer = organizer;
}
}
请注意两个@ JsonIgnore注释的字段，组织者和捐赠。我的目的是通过REST提供一个活动列表，忽略组织者和捐赠列表。我用cURL对此进行测试，如下所示：
curl -k -b cookie.txt https://localhost:8443/my-aktion/rest/organizer/campaign/list
输出结果为：
{"name":"testname","targetAmount":12.0,"donationMinimum":12.0,"amountDonatedSoFar":0.0,"account":{"name":"1212","nameOfBank":"1212","iban":"1212"},"id":1,"donations":[]}
首先让我感到奇怪的是：组织者被正确地忽略了，捐款也没有。并且，Wildfly（8.2.0）抛出以下例外：
11:17:38,282 ERROR [io.undertow.request] (default task-30) UT005023: Exception handling request to /my-aktion/rest/organizer/campaign/list: org.jboss.resteasy.spi.UnhandledException: Response is committed, can't handle exception
at org.jboss.resteasy.core.SynchronousDispatcher.writeException(SynchronousDispatcher.java:148) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.core.SynchronousDispatcher.writeResponse(SynchronousDispatcher.java:432) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:376) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:179) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:220) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51) [resteasy-jaxrs-3.0.10.Final.jar:]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) [jboss-servlet-api_3.1_spec-1.0.0.Final.jar:1.0.0.Final]
at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:61) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:56) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.server.handlers.DisableCacheHandler.handleRequest(DisableCacheHandler.java:33) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.security.handlers.AuthenticationConstraintHandler.handleRequest(AuthenticationConstraintHandler.java:51) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:45) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:63) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.security.ServletSecurityConstraintHandler.handleRequest(ServletSecurityConstraintHandler.java:56) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:58) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:70) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.security.handlers.SecurityInitialHandler.handleRequest(SecurityInitialHandler.java:76) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:261) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:247) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:76) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:166) [undertow-servlet-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.server.Connectors.executeRootHandler(Connectors.java:197) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:759) [undertow-core-1.1.0.Final.jar:1.1.0.Final]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [rt.jar:1.8.0_31]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [rt.jar:1.8.0_31]
at java.lang.Thread.run(Thread.java:745) [rt.jar:1.8.0_31]
Caused by: com.fasterxml.jackson.databind.JsonMappingException: failed to lazily initialize a collection of role: de.dpunkt.myaktion.model.Campaign.donations, could not initialize proxy - no Session (through reference chain: java.util.ArrayList[0]->de.dpunkt.myaktion.model.Campaign["donations"])
at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:232) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:197) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.std.StdSerializer.wrapAndThrow(StdSerializer.java:187) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:647) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:152) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContentsUsing(CollectionSerializer.java:145) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContents(CollectionSerializer.java:87) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContents(CollectionSerializer.java:23) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.std.AsArraySerializerBase.serialize(AsArraySerializerBase.java:183) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:236) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ObjectWriter.writeValue(ObjectWriter.java:604) [jackson-databind-2.4.1.jar:2.4.1]
at org.jboss.resteasy.plugins.providers.jackson.ResteasyJackson2Provider.writeTo(ResteasyJackson2Provider.java:199) [resteasy-jackson2-provider-3.0.10.Final.jar:]
at org.jboss.resteasy.core.interception.AbstractWriterInterceptorContext.writeTo(AbstractWriterInterceptorContext.java:129) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.core.interception.ServerWriterInterceptorContext.writeTo(ServerWriterInterceptorContext.java:62) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.core.interception.AbstractWriterInterceptorContext.proceed(AbstractWriterInterceptorContext.java:118) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.security.doseta.DigitalSigningInterceptor.aroundWriteTo(DigitalSigningInterceptor.java:143) [resteasy-crypto-3.0.10.Final.jar:]
at org.jboss.resteasy.core.interception.AbstractWriterInterceptorContext.proceed(AbstractWriterInterceptorContext.java:122) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.plugins.interceptors.encoding.GZIPEncodingInterceptor.aroundWriteTo(GZIPEncodingInterceptor.java:100) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.core.interception.AbstractWriterInterceptorContext.proceed(AbstractWriterInterceptorContext.java:122) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.core.ServerResponseWriter.writeNomapResponse(ServerResponseWriter.java:99) [resteasy-jaxrs-3.0.10.Final.jar:]
at org.jboss.resteasy.core.SynchronousDispatcher.writeResponse(SynchronousDispatcher.java:427) [resteasy-jaxrs-3.0.10.Final.jar:]
... 35 more
Caused by: org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: de.dpunkt.myaktion.model.Campaign.donations, could not initialize proxy - no Session
at org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:575) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:214) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:554) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.collection.internal.AbstractPersistentCollection.read(AbstractPersistentCollection.java:142) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.collection.internal.PersistentBag.iterator(PersistentBag.java:294) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContents(CollectionSerializer.java:90) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContents(CollectionSerializer.java:23) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.std.AsArraySerializerBase.serialize(AsArraySerializerBase.java:183) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:505) [jackson-databind-2.4.1.jar:2.4.1]
at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:639) [jackson-databind-2.4.1.jar:2.4.1]
... 52 more
我看到一个错误，试图懒惰初始化捐赠集合，但为什么甚至尝试？那里的@JsonIgnore注释是不是要完全阻止这个？