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我假设问题涉及在 Grails 实例中创建 Groovy 控制台；正常的域对象查询工作正常，但尝试一对一地查询自引用会导致问题。

我有一个域类，如下所示：

package demo

class Foo {
    String name
    static hasMany = [substitutes: Foo]
    static constraints = {
    }
}

期间bootstrap，我创建了一个控制台来检查域对象：

import demo.Foo
import org.springframework.web.context.support.WebApplicationContextUtils
import org.codehaus.groovy.grails.commons.GrailsApplication
import grails.util.GrailsUtil
import groovy.ui.Console

class BootStrap {

    def init = { servletContext ->
        def one = new Foo([name: 'one'])
        def two = new Foo([name: 'two'])
        [one,two].each { it.save(failOnError: true, flush: true)}
        one.addToSubstitutes(two)
        one.save(failOnError: true, flush: true)

        def appCtx = WebApplicationContextUtils.getRequiredWebApplicationContext(servletContext)
        def grailsApp = appCtx.getBean(GrailsApplication.APPLICATION_ID);
        Binding b = new Binding();
        b.setVariable("ctx", appCtx);
        def console = new Console(grailsApp.classLoader, b);
        console.run()

        Foo.list().each{println it.name} 
        Foo.list().each{println it.substitutes} 
        println '--------------------------'
    }
    def destroy = {
    }
}

这将在控制台中打印以下内容：

one
two
[demo.Foo : 2]
null
--------------------------

在控制台中，我尝试重复这两个查询，这会引发异常：

groovy> import demo.Foo 
groovy> demo.Foo.list().each{println it.name} 
groovy> demo.Foo.list().each{println it.substitutes} 

one
two
Exception thrown

org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: demo.Foo.substitutes, no session or session was closed
    at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:383)
    at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:375)
    at org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:368)
    at org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.java:111)
    at org.hibernate.collection.PersistentSet.iterator(PersistentSet.java:186)
    at org.springsource.loaded.ri.ReflectiveInterceptor.jlrMethodInvoke(ReflectiveInterceptor.java:1243)
    at ConsoleScript2$_run_closure2.doCall(ConsoleScript2:3)
    at org.springsource.loaded.ri.ReflectiveInterceptor.jlrMethodInvoke(ReflectiveInterceptor.java:1243)
    at ConsoleScript2.run(ConsoleScript2:3)
    at org.springsource.loaded.ri.ReflectiveInterceptor.jlrMethodInvoke(ReflectiveInterceptor.java:1243)
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