java - Calendar.DATE 和 Calendar.DAY_OF_MONTH 有什么区别？

Question

我调用的时候有什么不同吗:

calendar.get(Calendar.DATE);
calendar.get(Calendar.DAY_OF_MONTH);
calendar.set(Calendar.DATE, day);
calendar.set(Calendar.DAY_OF_MONTH, day);

?

Answer 1

请参阅 java.util.Calendar 的 API 文档(强调我的):

public static final int DAY_OF_MONTH

Field number for get and set indicating the day of the month. This is a synonym for DATE. The first day of the month has value 1.

“Synonym ”表示一个意思相同的词。这两个常量表示同一事物并且可以互换。

此外，如果您查看代码，您会注意到这些常量定义了相同的值:

/**
 * Field number for <code>get</code> and <code>set</code> indicating the
 * day of the month. This is a synonym for <code>DAY_OF_MONTH</code>.
 * The first day of the month has value 1.
 *
 * @see #DAY_OF_MONTH
 */
public final static int DATE = 5;

/**
 * Field number for <code>get</code> and <code>set</code> indicating the
 * day of the month. This is a synonym for <code>DATE</code>.
 * The first day of the month has value 1.
 *
 * @see #DATE
 */
public final static int DAY_OF_MONTH = 5;