com.mongodb

枚举 CursorType

java.lang.Object

java.lang.Enum<CursorType>

com.mongodb.CursorType

所有已实现的接口:

java.io.Serializable, java.lang.Comparable<CursorType>

public enum CursorType
extends java.lang.Enum<CursorType>

An enumeration of cursor types.

从以下版本开始:

3.0

MongoDB documentation

OP_QUERY

枚举常量概要

枚举常量

枚举常量和说明
NonTailable A non-tailable cursor.
Tailable Tailable means the cursor is not closed when the last data is retrieved.
TailableAwait A tailable cursor with a built-in server sleep before returning an empty batch.

方法概要

限定符和类型	方法和说明
abstract boolean	isTailable() True if the cursor type is tailable.
static CursorType	valueOf(java.lang.String name) 返回带有指定名称的该类型的枚举常量。
static CursorType[]	values() 按照声明该枚举类型的常量的顺序, 返回 包含这些常量的数组。

从类继承的方法 java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

从类继承的方法 java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

枚举常量详细资料

NonTailable

public static final CursorType NonTailable

A non-tailable cursor. This is sufficient for a vast majority of uses.

Tailable

public static final CursorType Tailable

Tailable means the cursor is not closed when the last data is retrieved. Rather, the cursor marks the final object's position. You can resume using the cursor later, from where it was located, if more data were received. Like any "latent cursor", the cursor may become invalid at some point - for example if the final object it references were deleted.

TailableAwait

public static final CursorType TailableAwait

A tailable cursor with a built-in server sleep before returning an empty batch. In most cases this is preferred type of tailable cursor, as it is less resource intensive.

方法详细资料

values

public static CursorType[] values()

按照声明该枚举类型的常量的顺序, 返回 包含这些常量的数组。该方法可用于迭代 常量, 如下所示:

for (CursorType c : CursorType.values())
    System.out.println(c);

返回:

按照声明该枚举类型的常量的顺序返回的包含这些常量的数组

valueOf

public static CursorType valueOf(java.lang.String name)

返回带有指定名称的该类型的枚举常量。 字符串必须与用于声明该类型的枚举常量的 标识符完全匹配。(不允许有多余 的空格字符。)

参数:

name - 要返回的枚举常量的名称。

返回:

返回带有指定名称的枚举常量

抛出:

java.lang.IllegalArgumentException - 如果该枚举类型没有带有指定名称的常量

java.lang.NullPointerException - 如果参数为空值

isTailable

public abstract boolean isTailable()

True if the cursor type is tailable.

返回:

true if the cursor type is tailable