Java 如何使用@DateTimeFormat 以弹簧形式绑定日期字段？
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How to bind date field in spring form using @DateTimeFormat?
提问by s0vet
I am looking for solution with my current problem. I have a classic POJO mapped by Hibernate with Datevariable.
我正在寻找解决我当前问题的方法。我有一个由 Hibernate 用Date变量映射的经典 POJO 。
@Entity
@Table(name="record")
public class Record implements Serializable {
@Column(name = Record.COLUMN_CREATED)
@Temporal(javax.persistence.TemporalType.TIMESTAMP)
@DateTimeFormat(pattern="dd.MM.yyyy hh:mm")
private Date created;
public Date getCreated() {
return created;
}
public void setCreated(Date created) {
this.created = created;
}
}
This entity is saved in MySQL database in TIMESTAMP variable (2013-09-25 22:13:18.000).
该实体保存在 MySQL 数据库中的 TIMESTAMP 变量 (2013-09-25 22:13:18.000) 中。
I am using Spring form to show data saved in my POJO.
我正在使用 Spring 表单来显示保存在我的 POJO 中的数据。
<form:form method="post" commandName="record" action="record/update.htm">
<table>
<tr>
<td><form:label path="<%=Record.COLUMN_CREATED%>"><spring:message code="administration.record.created"/>:</form:label></td>
<td><form:input path="<%=Record.COLUMN_CREATED%>"/></td>
</tr>
</table>
</form:form>
My problem is, when I want to edit this POJO and I send it into spring form to show, I get Date as 2013-09-25 22:13:18.000, exactly in the same format as MySQL timestamp. But I want to get this Date formated according the pattern, which I set using @DateTimeFormat annotation.
我的问题是，当我想编辑这个 POJO 并将其发送到 spring 形式以显示时，我得到的日期为 2013-09-25 22:13:18.000，与 MySQL 时间戳的格式完全相同。但是我想根据我使用 @DateTimeFormat 注释设置的模式来格式化这个日期。
Can someone tells me, what am I doing wrong ? Many thanks, Ondrej.
有人可以告诉我，我做错了什么吗？非常感谢，Ondrej。
EDIT: I have the @InitBinderalready, but it works only when I am creating a new object through the form, so it cast Stringto Date. But when I want to fill the form inputs with existing data in DB, it doesnt work.
编辑：我已经@InitBinder有了，但它仅在我通过表单创建新对象时才有效，因此它强制转换String为Date. 但是当我想用数据库中的现有数据填充表单输入时，它不起作用。
@InitBinder
public void initBinder(WebDataBinder binder) {
SimpleDateFormat sdf = new SimpleDateFormat("dd.MM.yyyy h:mm");
sdf.setLenient(true);
binder.registerCustomEditor(Date.class, new CustomDateEditor(sdf, true));
binder.registerCustomEditor(String.class, new StringTrimmerEditor(true));
}
I am using Spring 3.1.1.RELEASE without Joda time, just ordinary java.util.Date.
我正在使用没有 Joda 时间的 Spring 3.1.1.RELEASE，只是普通的 java.util.Date。
<mvc:annotation-driven/>in dispatcher-servlet.xml is set properly. When I use debugger I can see, that while creating the new object from form input values a method setAsText(String text)of CustomDateEditoris used. I expect that the second method, String getAsText()will be used for formating Data to String while filling the form inputs. But, it doesnt !
<mvc:annotation-driven/>在 dispatcher-servlet.xml 中设置正确。当我使用调试器我所看到的，而产生从表单输入新对象值的方法setAsText(String text)的CustomDateEditor使用。我希望第二种方法String getAsText()将用于在填写表单输入时将数据格式化为字符串。但是，它没有！
回答by Sotirios Delimanolis
The @DateTimeFormat(pattern="dd.MM.yyyy hh:mm")annotation is basically saying that when you get a Stringin the particular pattern, convert it into
该@DateTimeFormat(pattern="dd.MM.yyyy hh:mm")注释基本上是说，当你得到一个String在特定的模式，将其转换成
java.util.Date,java.util.Calendar,java.long.Long, or Joda Time fields.
java.util.Date、java.util.Calendar、java.long.Long或 Joda 时间字段。
In your case, it's a java.util.Date.
在你的情况下，它是一个java.util.Date.
When you do something like
当你做类似的事情时
<spring:message code="administration.record.created"/>:</form:label>
You're just calling toString()on the createdDateobject. The Dateclass internally uses its own format when returning a String in toString()and that's what you see.
你只是叫toString()上createdDate对象。在Date返回的字符串时类在内部使用它自己的格式toString()，这就是你所看到的。
Consider using the fmt:formatDatetag from JSTL.
考虑使用fmt:formatDate来自 JSTL的标记。
