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Initialize lazy collections

Tags:

java

hibernate

lazy-loading

I'm developing a Struts2 + Spring + Hibernate webapp and I need to initialize a lazy collection after retrieving an object or a collection of that object.

Use case

I have a team model with a relation eagerly loaded called employees (I think it's obvious that this is a collection). In turn, employee model has a lazy relation registry that I need just for some specific actions so I don't need at all to load it eagerly.

Now. I call my teamService (injected to my Struts2 controller with Spring) in order to retrieve a specific teamItem which has already his collection employees loaded. Now it's time to load for each employee its registry relation.

Using the employeeService (also this injected to my Struts2 controller with Spring) I call the initializeCollections() method of his DAO that should load the lazy collection calling

Hibernate.initialize(employee.getRegistry());

When I perform this action a org.hibernate.LazyInitializationException: could not initialize proxy - no Session exception is thrown.

stack trace:

at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:167) ~[hibernate-core-3.6.10.Final.jar:3.6.10.Final]
at org.hibernate.Hibernate.initialize(Hibernate.java:414) ~[hibernate-core-3.6.10.Final.jar:3.6.10.Final]
at web.bkgd.simba.dao.registry.RegistryEmployeeDAO.initializeCollections(RegistryEmployeeDAO.java:438) ~[RegistryEmployeeDAO.class:?]
at web.bkgd.simba.service.abstractions.BaseService.initializeCollections(BaseService.java:142) ~[BaseService.class:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.7.0_79]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) ~[?:1.7.0_79]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.7.0_79]
at java.lang.reflect.Method.invoke(Method.java:606) ~[?:1.7.0_79]
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317) ~[spring-aop-4.1.0.RELEASE.jar:4.1.0.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190) ~[spring-aop-4.1.0.RELEASE.jar:4.1.0.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) ~[spring-aop-4.1.0.RELEASE.jar:4.1.0.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:98) ~[spring-tx-4.1.0.RELEASE.jar:4.1.0.RELEASE]
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:266) ~[spring-tx-4.1.0.RELEASE.jar:4.1.0.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95) ~[spring-tx-4.1.0.RELEASE.jar:4.1.0.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.1.0.RELEASE.jar:4.1.0.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207) ~[spring-aop-4.1.0.RELEASE.jar:4.1.0.RELEASE]
at com.sun.proxy.$Proxy1302.initializeCollections(Unknown Source) ~[?:?]
at web.bkgd.simba.controller.ajax.agenda.TeamController.doSomething(TeamController.java:177) ~[AjaxTeamController.class:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.7.0_79]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) ~[?:1.7.0_79]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.7.0_79]
at java.lang.reflect.Method.invoke(Method.java:606) ~[?:1.7.0_79]
at ognl.OgnlRuntime.invokeMethod(OgnlRuntime.java:870) ~[ognl-3.0.6.jar:?]
at ognl.OgnlRuntime.callAppropriateMethod(OgnlRuntime.java:1293) ~[ognl-3.0.6.jar:?]
at ognl.ObjectMethodAccessor.callMethod(ObjectMethodAccessor.java:68) ~[ognl-3.0.6.jar:?]
at com.opensymphony.xwork2.ognl.accessor.XWorkMethodAccessor.callMethodWithDebugInfo(XWorkMethodAccessor.java:117) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.ognl.accessor.XWorkMethodAccessor.callMethod(XWorkMethodAccessor.java:108) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at ognl.OgnlRuntime.callMethod(OgnlRuntime.java:1369) ~[ognl-3.0.6.jar:?]
at ognl.ASTMethod.getValueBody(ASTMethod.java:90) ~[ognl-3.0.6.jar:?]
at ognl.SimpleNode.evaluateGetValueBody(SimpleNode.java:212) ~[ognl-3.0.6.jar:?]
at ognl.SimpleNode.getValue(SimpleNode.java:258) ~[ognl-3.0.6.jar:?]
at ognl.Ognl.getValue(Ognl.java:494) ~[ognl-3.0.6.jar:?]
at ognl.Ognl.getValue(Ognl.java:458) ~[ognl-3.0.6.jar:?]
at com.opensymphony.xwork2.ognl.OgnlUtil$2.execute(OgnlUtil.java:309) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.ognl.OgnlUtil.compileAndExecute(OgnlUtil.java:340) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.ognl.OgnlUtil.getValue(OgnlUtil.java:307) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:423) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:287) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:250) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at web.bkgd.simba.utility.interceptors.SessionCleanInterceptor.intercept(SessionCleanInterceptor.java:86) ~[SessionCleanInterceptor.class:?]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.interceptor.DeprecationInterceptor.intercept(DeprecationInterceptor.java:41) ~[struts2-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256) ~[struts2-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:167) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:76) ~[struts2-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:191) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:73) ~[struts2-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.interceptor.DateTextFieldInterceptor.intercept(DateTextFieldInterceptor.java:125) ~[struts2-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:91) ~[struts2-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:253) ~[struts2-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:145) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:171) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:139) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164) ~[struts2-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:193) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) ~[xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:189) [xwork-core-2.3.24.1.jar:2.3.24.1]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) [xwork-core-2.3.24.1.jar:2.3.24.1]
at web.bkgd.simba.utility.interceptors.LoginInterceptor.intercept(LoginInterceptor.java:113) [LoginInterceptor.class:?]
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) [xwork-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54) [struts2-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:564) [struts2-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:81) [struts2-core-2.3.24.1.jar:2.3.24.1]
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:99) [struts2-core-2.3.24.1.jar:2.3.24.1]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) [catalina.jar:7.0.61]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [catalina.jar:7.0.61]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) [catalina.jar:7.0.61]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) [catalina.jar:7.0.61]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505) [catalina.jar:7.0.61]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170) [catalina.jar:7.0.61]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) [catalina.jar:7.0.61]
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950) [catalina.jar:7.0.61]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) [catalina.jar:7.0.61]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:423) [catalina.jar:7.0.61]
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1079) [tomcat-coyote.jar:7.0.61]
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:620) [tomcat-coyote.jar:7.0.61]
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318) [tomcat-coyote.jar:7.0.61]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [?:1.7.0_79]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [?:1.7.0_79]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-coyote.jar:7.0.61]
at java.lang.Thread.run(Thread.java:745) [?:1.7.0_79]
  • Am I doing something wrong?
  • Is there a different way to load that lazy collection?

EDIT 01-12-2015

I've tried to follow Predrag Maric answer and I have a little edit to do since seems still not working.

So:

  1. Implement Open Session in View pattern

No way. This solution may cause a very deep loading of the relations expecially for JSON serialization. Of course I can always define the <param name="includeProperties"> tag and load just what I need, but I'm still a little scared of the performances.

  1. Initialize whatever you need in the first service

And here is the point. I've changed my action and DAO structure in order to implement this function. I've used a little of reflection in order to create a general method that I can use in every single DAO of my application.

How it works is very simple:

Example

INPUT:

  • beanClass: Team
  • model: team with no relations loaded
  • relations: List:{"relation", "relation.childRelation.grandChildRelation"}

The method for the first string simply calls Hibernate.initialize() method and for the second one splits the string in order to load:

  • realation, returns initializeRelations(relation.class, relation, "childRelation.grandChildRelation");
  • childRelation, returns initializeRelations(childRelation.class, childRelation, "grandChildRelation");
  • grandChildRelation;

Here you have the code:

TEAM DAO

These methods are called after a team bean or a list of team beans has been loaded from the database

/**
 * Initialize relations. This method returns true if a correct
 * initialization of the relation has been made by hibernate, false in any
 * other case. If the relations object is a List, the method recursively
 * call himself in order to initialize every single instance of the list.
 * If the relations string contains a "." it means that a grandchild
 * relation has to be loaded.
 *
 * @param beanClass
 * @param model
 * @param relations
 * @return boolean
 */
public boolean initializeRelations(Class beanClass, BaseModel model, Object relations) {
    // Check if relations is a List
    if (relations instanceof List) {
        // Recursively call initializeRelations
        for (String relation : (List<String>) relations) {
            return initializeRelations(beanClass, model, relation);
        }
    } else if (relations instanceof String) {
        // If relations contains "." then a grandChild relation has to be loaded.
        if (((String) relations).contains(".")) {
            String[] childRelations = ((String) relations).split("\\.");

            // Initialize the child relation
            Object newChildRelations = initializeRelation(beanClass, model, childRelations[0]);

            if (newChildRelations == null) {
                return false;
            } else if (newChildRelations instanceof BaseModel) {
                initializeRelations(newChildRelations.getClass(), model, (Object[]) Arrays.copyOfRange(childRelations, 1, childRelations.length));
            } else if (newChildRelations instanceof List) {
                for (Object newChildRelation : childRelations) {
                    initializeRelations(newChildRelation.getClass(), model, (Object[]) Arrays.copyOfRange(childRelations, 1, childRelations.length));
                }
            }
        } else {
            Object newChildRelations = initializeRelation(beanClass, model, (String) relations);

            return newChildRelations == null;
        }
    }

    return false;
}

private Object initializeRelation(Class beanClass, BaseModel model, String relation) {
    try {
        for (PropertyDescriptor pd : Introspector.getBeanInfo(beanClass).getPropertyDescriptors()) {
            if (pd.getReadMethod() != null && !"class".equals(pd.getName()) && relation.toLowerCase().equals(pd.getName().toLowerCase()) && pd.getReadMethod().invoke(model) == null) {
                Hibernate.initialize(pd.getReadMethod().invoke(model));

                return pd.getReadMethod().invoke(model);
            }
        }
    } catch (IntrospectionException ex) {
        LOG.warn("Cannot initialize ralation", ex);
    } catch (HibernateException | IllegalAccessException | IllegalArgumentException | InvocationTargetException ex) {
        LOG.warn("Cannot initialize ralation", ex);
    }
    return null;
}

But what I see in my log is that just the first relation is loaded

[DEBUG] 01-12-2015 14:06:52 Controller - relation: Employee{data1="data1", data2="data2", data3="data3", data4="data4", data5="data5"}
[DEBUG] 01-12-2015 14:06:52 Controller - child: [!!!model.Registry_$$_javassist_17@75ce9b7d=>org.hibernate.LazyInitializationException:could not initialize proxy - no Session!!!]
like image 243
IlGala Avatar asked Nov 27 '15 11:11

IlGala

People also ask

How do you initialize a lazy?

Implementing a Lazy-Initialized Property To implement a public property by using lazy initialization, define the backing field of the property as a Lazy<T>, and return the Value property from the get accessor of the property. The Value property is read-only; therefore, the property that exposes it has no set accessor.

How do I fix lazy initialization exception?

The right way to fix a LazyInitializationException is to fetch all required associations within your service layer. The best option for that is to load the entity with all required associations in one query.

What does lazy initialization mean in Hibernate?

Lazy loading in Hibernate means fetching and loading the data, only when it is needed, from a persistent storage like a database. Lazy loading improves the performance of data fetching and significantly reduces the memory footprint.

2 Answers

I had the some problem a few months ago. I have solved it setting a parameter in my session factory builder.

Try setting the parameter "hibernate.enable_lazy_load_no_trans" to your hibernate config.

sfBuilder.getProperties().put("hibernate.enable_lazy_load_no_trans",
            "true");

This parameter solved my problem. Hope it helps.

Edited: Use with caution. Check out this post.

like image 57
Rodrigo Almeida Avatar answered Oct 18 '22 13:10

Rodrigo Almeida

Yes, you can use Hibernate.initialize() to initialize lazy relations, but this requires an active Hibernate session. You are

  1. Calling teamService from the controller (one transaction)
  2. Calling employeeService with the results of the first call (another transaction)

Your entities are detached from the session after the first call (correct me if I'm wrong, I assumed you've configured transactions on service layer), so this fails. You should either

  1. Implement Open Session in View pattern
  2. Initialize whatever you need in the first service

As for 2., if this service is used in other places which don't need employee.registry initialized, you can use a parameter to control initialization

teamService.getTeam(id, init);
// and then in getTeam()
if (init) {
    Hibernate.initialize(employee.getRegistry());
}

To make this more generic, you can create a InitConfig class, which would be passed to each service that needs this kind of behavior. You just add specific parameters in it as you need them.

public class InitConfig {
    ...
    private boolean initRegistry;
    ...
}

teamService.getTeam(id, initConfig);
// and then in getTeam()
if (initConfig.getInitRegistry()) {
    Hibernate.initialize(employee.getRegistry());
}
like image 24
Predrag Maric Avatar answered Oct 18 '22 13:10

Predrag Maric
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