grails - Grails IndexOutOfBoundsException

Question

我在Grails中有以下代码:

public LibraryItem createLibraryItemWithValues(ProjectItem projectItem) {
    def libraryitem = new LibraryItem ()
    libraryitem.name = projectItem.name
    libraryitem.itemtype = projectItem.itemtype.itemtype
    libraryitem.description = projectItem.description
    List<LibraryCategoryValue> libCatValues = new ArrayList<LibraryCategoryValue>();
    for (def pcv : projectItem.categoryvalues) {
        libCatValues.add(pcv.librarycategoryvalue);
    }
    if (libraryitem.id != null && !libraryitem.isAttached()) {
        libraryitem.attach()
    }
    libCatValues.each{
        it.addToLibraryitems(libraryitem)
    }
    return libraryitem.save()
}

类LibraryCategoryValue

package ch.fhnw.accelerom.project.library

import ch.fhnw.accelerom.project.ItemType
import ch.fhnw.accelerom.project.TranslatableObject


class LibraryCategoryValue extends TranslatableObject {
  SortedSet<LibraryItem> libraryitems

  static belongsTo = [librarycategory:LibraryCategory]
  static hasMany = [libraryitems: LibraryItem]
  static constraints = {
  }
}

我的问题是，当我在服务中运行此代码时，我得到了异常消息“IndexOutOfBoundsException”和detailMessage“索引:1，大小为0”，并且抑制了异常“Collections $ UnmodifiableRandomAccessList”的值为“size = 0”，但没有异常，当我在 Controller 中运行此代码时。异常来自命令it.addToLibraryitems(libraryitem)，响应性很强，当我注释此行时，不会发生异常。有人可以给我提示，可能是什么问题？

提前致谢。

编辑:

我现在在类中初始化了libraryitems

SortedSet<LibraryItem> libraryitems = []

但是现在启动应用程序时出现以下错误

ERROR context.GrailsContextLoader  - Error initializing the application: Error creating bean with name 'transactionManagerPostProcessor': Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager': Cannot resolve reference to bean 'sessionFactory' while setting bean property 'sessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is org.hibernate.InstantiationException: could not instantiate test objectch.fhnw.accelerom.project.library.LibraryCategoryValue
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManagerPostProcessor': Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager': Cannot resolve reference to bean 'sessionFactory' while setting bean property 'sessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is org.hibernate.InstantiationException: could not instantiate test objectch.fhnw.accelerom.project.library.LibraryCategoryValue
    at java.util.concurrent.FutureTask.run(FutureTask.java:262)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager': Cannot resolve reference to bean 'sessionFactory' while setting bean property 'sessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is org.hibernate.InstantiationException: could not instantiate test objectch.fhnw.accelerom.project.library.LibraryCategoryValue
    ... 4 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is org.hibernate.InstantiationException: could not instantiate test objectch.fhnw.accelerom.project.library.LibraryCategoryValue
    ... 4 more
Caused by: org.hibernate.InstantiationException: could not instantiate test objectch.fhnw.accelerom.project.library.LibraryCategoryValue
    ... 4 more
Caused by: java.lang.reflect.InvocationTargetException
    ... 4 more
Caused by: org.codehaus.groovy.runtime.typehandling.GroovyCastException: Cannot cast object '[]' with class 'java.util.ArrayList' to class 'java.util.SortedSet' due to: groovy.lang.GroovyRuntimeException: Could not find matching constructor for: java.util.SortedSet()
    at ch.fhnw.accelerom.project.library.LibraryCategoryValue.<init>(LibraryCategoryValue.groovy:7)
    ... 4 more

编辑2:

我也尝试用

SortedSet<LibraryItem> libraryitems = new TreeSet<LibraryItem>()

但是，我又回到了第一个异常“IndexOutOfBoundsException”。我很好奇，当 Controller 中有此代码时，为什么没有问题。在这种情况下，服务和 Controller 之间有什么区别？

Answer 1

尝试使用事务服务方法:

import grails.transaction.Transactional

class LibraryService {

    @Transactional
    public LibraryItem createLibraryItemWithValues(ProjectItem projectItem) {
        def libraryitem = new LibraryItem()

        libraryitem.name = projectItem.name
        libraryitem.itemtype = projectItem.itemtype.itemtype
        libraryitem.description = projectItem.description

        projectItem.categoryvalues*.librarycategoryvalue.each {
            it.addToLibraryitems(libraryitem)
        }

        return libraryitem.save()
    }
}

由于您正在创建新的 LibraryItem，因此在保存之前，其ID始终为null。在大多数情况下，您不需要使用 attach()，因此我删除了所有这些代码。