Okay, let's take a moment or two to review. The enumerated, or enum, data type in Java is used to describe a specific set of values for a variable. They are static and final, which really means they can't be changed, and type-safe, which means there's no way to assign a value...
*@sinceJava Persistence 1.0*/publicenumEnumType {/**Persist enumerated type property or field as an integer.*/ORDINAL,/**Persist enumerated type property or field as a string.*/STRING } 如果不使用该注解,就是在上面说的默认的情况是使用Enum中的ordinal属性来完成,所以关于这部分就不详细阐述了。 ...
The identifier enum might well be in programs that use the older class java.util.Enumeration. That class has nothing to do with the enum type, but is a way of iterating through all the objects in a data structure class. Many people (including me) declared variables such as java.util.Enu...
在Java中Enum是一种“奇葩”的存在,“奇葩”不代表没用,对于这种比较特殊的存在,hibernate会有很多种选择来完成Enum类型字段的映射,首先要说明的是在hibernate都是把Enum类型的字段映射成基本类型的字段,并且我这里不使用任何配置文件来配置映射,而是统一使用注解这种方式来完成映射。 注意...
Specifies that a persistent property or field should be persisted as a enumerated type. The Enumerated annotation may be used in conjunction with the Basic annotation, or in conjunction with the ElementCollection annotation when the element collection value is of basic type. If the enumerated type ...
enumerated typeis an abstract data type used to model an attribute that has a specific number of options (or identifiers) . Eg : enum cardsuit { CLUBS, DIAMONDS, HEARTS, SPADES }; However at runtime the the enum will be implemented with an interger. ...
②@Temporal注解:在核心的JavaAPI中并没有定义时间精度,因此处理时间类型数据时,需要定义将其存储在数据库中所预期的精度。在数据库中,表示时间类型的数据有date、time、timestamp,默认情况下,即不写@Temporal情况下是timestamp. ③@Column注解:在建表时会用到,name(列名)、unique(唯一约束,类似主键特性,但是一个...
How to define an enumerated type (enum) in C - An enumerated type declares an optional type name and a set of zero or more identifiers that can be used as values of the type. Each enumerator is a constant whose type is the enumeration. For example, if y
<!-- Drop and re-create the database schema on startup --> <property name="hbm2ddl.auto">create</property><!-- 当没有这张表时,自动创建 ,create最常用--> <!-- update: 在编程的过程中,需要向表中添加新的字段,不用在数据库中添加新字段,程序运行起来后,会自动添加--> ...
本文整理了Java中org.activityinfo.model.type.enumerated.EnumType.getEffectivePresentation()方法的一些代码示例,展示了EnumType.getEffectivePresentation()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台,是从一些精选项目中提取出来的代码,具有较强的参考意义,能在一定程度帮忙到你。EnumType.getEff...