Membership (Apache Tomcat 8.0.53 API Documentation)

java.lang.Object
- org.apache.catalina.tribes.membership.Membership

All Implemented Interfaces:

java.lang.Cloneable
```
public class Membership
extends java.lang.Object
implements java.lang.Cloneable
```
A membership implementation using simple multicast. This is the representation of a multicast membership. This class is responsible for maintaining a list of active cluster nodes in the cluster. If a node fails to send out a heartbeat, the node will be dismissed.

Author:

Peter Rossbach

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

protected static class Membership.MbrEntry
Inner class that represents a member entry

Nested Classes
Modifier and Type	Class and Description
`protected static class`	`Membership.MbrEntry` Inner class that represents a member entry

Field Summary

Fields
Modifier and Type	Field and Description
`protected static Member[]`	`EMPTY_MEMBERS`
`protected Member`	`local` The local member.
`protected java.util.HashMap<Member,Membership.MbrEntry>`	`map` A map of all the members in the cluster.
`protected java.util.Comparator<Member>`	`memberComparator` Comparator for sorting members by alive time.
`protected Member[]`	`members` A list of all the members in the cluster.

Constructor Summary

Constructors
Constructor and Description
`Membership(Member local)`
`Membership(Member local, boolean includeLocal)` Constructs a new membership
`Membership(Member local, java.util.Comparator<Member> comp)`
`Membership(Member local, java.util.Comparator<Member> comp, boolean includeLocal)`

Method Summary

Methods
Modifier and Type	Method and Description
`Membership.MbrEntry`	`addMember(Member member)` Add a member to this component and sort array with memberComparator
`java.lang.Object`	`clone()`
`boolean`	`contains(Member mbr)`
`Member[]`	`expire(long maxtime)` Runs a refresh cycle and returns a list of members that has expired.
`Member`	`getMember(Member mbr)`
`protected Membership.MbrEntry[]`	`getMemberEntries()` Deprecated. Unused. Will be removed in Tomcat 8.5.x.
`Member[]`	`getMembers()` Returning a list of all the members in the membership.
`boolean`	`hasMembers()` Returning that service has members or not.
`boolean`	`memberAlive(Member member)` Notify the membership that this member has announced itself.
`void`	`removeMember(Member member)` Remove a member from this component.
`void`	`reset()` Reset the membership and start over fresh. i.e., delete all the members and wait for them to ping again and join this membership.

Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - EMPTY_MEMBERS
```
protected static final Member[] EMPTY_MEMBERS
```
  - local
```
protected final Member local
```
    The local member.
  - map
```
protected java.util.HashMap<Member,Membership.MbrEntry> map
```
    A map of all the members in the cluster.
  - members
```
protected volatile Member[] members
```
    A list of all the members in the cluster.
  - memberComparator
```
protected final java.util.Comparator<Member> memberComparator
```
    Comparator for sorting members by alive time.
- Constructor Detail
  - Membership
```
public Membership(Member local,
          boolean includeLocal)
```
    Constructs a new membership
    
    Parameters:
    local - - has to be the name of the local member. Used to filter the local member from the cluster membership
    includeLocal - - TBA
  - Membership
```
public Membership(Member local)
```
  - Membership
```
public Membership(Member local,
          java.util.Comparator<Member> comp)
```
  - Membership
```
public Membership(Member local,
          java.util.Comparator<Member> comp,
          boolean includeLocal)
```
- Method Detail
  - clone
```
public java.lang.Object clone()
```
    Overrides:
    
    clone in class java.lang.Object
  - reset
```
public void reset()
```
    Reset the membership and start over fresh. i.e., delete all the members and wait for them to ping again and join this membership.
  - memberAlive
```
public boolean memberAlive(Member member)
```
    Notify the membership that this member has announced itself.
    
    Parameters:
    member - - the member that just pinged us
    
    Returns:
    - true if this member is new to the cluster, false otherwise.
    - false if this member is the local member or updated.
  - addMember
```
public Membership.MbrEntry addMember(Member member)
```
    Add a member to this component and sort array with memberComparator
    
    Parameters:
    member - The member to add
    
    Returns:
    The member entry created for this new member.
  - removeMember
```
public void removeMember(Member member)
```
    Remove a member from this component.
    
    Parameters:
    member - The member to remove
  - expire
```
public Member[] expire(long maxtime)
```
    Runs a refresh cycle and returns a list of members that has expired. This also removes the members from the membership, in such a way that getMembers() = getMembers() - expire()
    
    Parameters:
    maxtime - - the max time a member can remain unannounced before it is considered dead.
    
    Returns:
    the list of expired members
  - hasMembers
```
public boolean hasMembers()
```
    Returning that service has members or not.
    
    Returns:
    true if there are one or more members, otherwise false
  - getMember
```
public Member getMember(Member mbr)
```
  - contains
```
public boolean contains(Member mbr)
```
  - getMembers
```
public Member[] getMembers()
```
    Returning a list of all the members in the membership. We not need a copy: add and remove generate new arrays.
    
    Returns:
    An array of the current members
  - getMemberEntries
```
@Deprecated
protected Membership.MbrEntry[] getMemberEntries()
```
    Deprecated. Unused. Will be removed in Tomcat 8.5.x.
    
    Get a copy from all member entries.

Class Membership

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

EMPTY_MEMBERS

local

map

members

memberComparator

Constructor Detail

Membership

Membership

Membership

Membership

Method Detail

clone

reset

memberAlive

addMember

removeMember

expire

hasMembers

getMember

contains

getMembers

getMemberEntries