STATE_TRANSFER

java.lang.Object
- com.fr.third.jgroups.stack.Protocol
- - com.fr.third.jgroups.protocols.pbcast.STATE_TRANSFER

所有已实现的接口:

ProcessingQueue.Handler<Address>
```
public class STATE_TRANSFER
extends Protocol
implements ProcessingQueue.Handler<Address>
```
STATE_TRANSFER protocol based on byte array transfer. A state request is sent to a chosen member (coordinator if null). That member makes a copy D of its current digest and asks the application for a copy of its current state S. Then the member returns both S and D to the requester. The requester first sets its digest to D and then returns the state to the application.

作者:

Bela Ban

另请参阅:
STATE, STATE_SOCK

嵌套类概要

嵌套类
限定符和类型类和说明

static class STATE_TRANSFER.StateHeader
Wraps data for a state request/response.

嵌套类
限定符和类型	类和说明
`static class`	`STATE_TRANSFER.StateHeader` Wraps data for a state request/response.

字段概要

字段
限定符和类型	字段和说明
`protected double`	`avg_state_size`
`protected boolean`	`flushProtocolInStack`
`protected Address`	`local_addr`
`protected java.util.List<Address>`	`members`
`protected java.util.concurrent.atomic.AtomicLong`	`num_bytes_sent`
`protected java.util.concurrent.atomic.AtomicInteger`	`num_state_reqs`
`protected long`	`start`
`protected ProcessingQueue<Address>`	`state_requesters` List of members requesting state
`protected long`	`stop`
`protected View`	`view`
`protected boolean`	`waiting_for_state_response` set to true while waiting for a STATE_RSP

从类继承的字段 com.fr.third.jgroups.stack.Protocol
down_prot, ergonomics, id, log, name, stack, stats, up_prot

构造器概要

构造器
构造器和说明

STATE_TRANSFER()

构造器
构造器和说明
`STATE_TRANSFER()`

方法概要

方法
限定符和类型	方法和说明
`void`	`closeBarrierAndSuspendStable()`
`protected void`	`closeHoleFor(Address member)`
`protected Address`	`determineCoordinator()` Return the first element of members which is not me.
`java.lang.Object`	`down(Event evt)` An event is to be sent down the stack.
`double`	`getAverageStateSize()`
`long`	`getNumberOfStateBytesSent()`
`int`	`getNumberOfStateRequests()`
`protected void`	`getStateFromApplication(Address requester, Digest digest)`
`void`	`handle(Address state_requester)`
`protected void`	`handleException(java.lang.Throwable exception)`
`protected void`	`handleStateReq(Address requester)`
`protected void`	`handleStateRsp(Digest digest, Address sender, byte[] state)` Set the digest and the send the state up to the application
`protected void`	`handleViewChange(View v)`
`void`	`init()` Called after instance has been created (null constructor) and before protocol is started.
`protected boolean`	`isDigestNeeded()` When FLUSH is used we do not need to pass digests between members see JGroups/doc/design/PartialStateTransfer.txt see JGroups/doc/design/FLUSH.txt
`void`	`openBarrier()`
`void`	`openBarrierAndResumeStable()`
`protected void`	`punchHoleFor(Address member)`
`java.util.List<java.lang.Integer>`	`requiredDownServices()` List of events that are required to be answered by some layer below
`void`	`resetStats()`
`void`	`resumeStable()`
`protected void`	`sendException(Address requester, java.lang.Throwable exception)`
`void`	`start()` This method is called on a `Channel.connect(String)`.
`void`	`stop()` This method is called on a `Channel.disconnect()`.
`java.lang.Object`	`up(Event evt)` An event was received from the layer below.

从类继承的方法 com.fr.third.jgroups.stack.Protocol
accept, destroy, dumpStats, enableStats, getConfigurableObjects, getDownProtocol, getDownServices, getId, getIdsAbove, getLevel, getName, getProtocolStack, getSocketFactory, getThreadFactory, getTransport, getUpProtocol, getUpServices, getValue, isErgonomics, level, parse, printStats, providedDownServices, providedUpServices, requiredUpServices, resetStatistics, setDownProtocol, setErgonomics, setId, setLevel, setProtocolStack, setSocketFactory, setUpProtocol, setValue, setValues, statsEnabled, up

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 字段详细资料
  - start
```
protected long start
```
  - stop
```
protected long stop
```
  - num_state_reqs
```
protected final java.util.concurrent.atomic.AtomicInteger num_state_reqs
```
  - num_bytes_sent
```
protected final java.util.concurrent.atomic.AtomicLong num_bytes_sent
```
  - avg_state_size
```
protected double avg_state_size
```
  - local_addr
```
protected Address local_addr
```
  - view
```
protected volatile View view
```
  - members
```
protected final java.util.List<Address> members
```
  - state_requesters
```
protected final ProcessingQueue<Address> state_requesters
```
    List of members requesting state
  - waiting_for_state_response
```
protected volatile boolean waiting_for_state_response
```
    set to true while waiting for a STATE_RSP
  - flushProtocolInStack
```
protected boolean flushProtocolInStack
```
- 构造器详细资料
  - STATE_TRANSFER
```
public STATE_TRANSFER()
```
- 方法详细资料
  - getNumberOfStateRequests
```
public int getNumberOfStateRequests()
```
  - getNumberOfStateBytesSent
```
public long getNumberOfStateBytesSent()
```
  - getAverageStateSize
```
public double getAverageStateSize()
```
  - requiredDownServices
```
public java.util.List<java.lang.Integer> requiredDownServices()
```
    从类复制的说明: Protocol
    
    List of events that are required to be answered by some layer below
    
    覆盖:
    
    requiredDownServices 在类中 Protocol
  - resetStats
```
public void resetStats()
```
    覆盖:
    
    resetStats 在类中 Protocol
  - init
```
public void init()
          throws java.lang.Exception
```
    从类复制的说明: Protocol
    
    Called after instance has been created (null constructor) and before protocol is started. Properties are already set. Other protocols are not yet connected and events cannot yet be sent.
    
    覆盖:
    
    init 在类中 Protocol
    
    抛出:
    
    java.lang.Exception - Thrown if protocol cannot be initialized successfully. This will cause the ProtocolStack to fail, so the channel constructor will throw an exception
  - start
```
public void start()
           throws java.lang.Exception
```
    从类复制的说明: Protocol
    
    This method is called on a Channel.connect(String). Starts work. Protocols are connected and queues are ready to receive events. Will be called from bottom to top. This call will replace the START and START_OK events.
    
    覆盖:
    
    start 在类中 Protocol
    
    抛出:
    
    java.lang.Exception - Thrown if protocol cannot be started successfully. This will cause the ProtocolStack to fail, so Channel.connect(String) will throw an exception
  - stop
```
public void stop()
```
    从类复制的说明: Protocol
    
    This method is called on a Channel.disconnect(). Stops work (e.g. by closing multicast socket). Will be called from top to bottom. This means that at the time of the method invocation the neighbor protocol below is still working. This method will replace the STOP, STOP_OK, CLEANUP and CLEANUP_OK events. The ProtocolStack guarantees that when this method is called all messages in the down queue will have been flushed
    
    覆盖:
    
    stop 在类中 Protocol
  - closeBarrierAndSuspendStable
```
public void closeBarrierAndSuspendStable()
```
  - openBarrierAndResumeStable
```
public void openBarrierAndResumeStable()
```
  - openBarrier
```
public void openBarrier()
```
  - resumeStable
```
public void resumeStable()
```
  - up
```
public java.lang.Object up(Event evt)
```
    从类复制的说明: Protocol
    
    An event was received from the layer below. Usually the current layer will want to examine the event type and - depending on its type - perform some computation (e.g. removing headers from a MSG event type, or updating the internal membership list when receiving a VIEW_CHANGE event). Finally the event is either a) discarded, or b) an event is sent down the stack using down_prot.down() or c) the event (or another event) is sent up the stack using up_prot.up().
    
    覆盖:
    
    up 在类中 Protocol
  - down
```
public java.lang.Object down(Event evt)
```
    从类复制的说明: Protocol
    
    An event is to be sent down the stack. The layer may want to examine its type and perform some action on it, depending on the event's type. If the event is a message MSG, then the layer may need to add a header to it (or do nothing at all) before sending it down the stack using down_prot.down(). In case of a GET_ADDRESS event (which tries to retrieve the stack's address from one of the bottom layers), the layer may need to send a new response event back up the stack using up_prot.up().
    
    覆盖:
    
    down 在类中 Protocol
  - isDigestNeeded
```
protected boolean isDigestNeeded()
```
    When FLUSH is used we do not need to pass digests between members
    see JGroups/doc/design/PartialStateTransfer.txt see JGroups/doc/design/FLUSH.txt
    
    返回:
    true if use of digests is required, false otherwise
  - punchHoleFor
```
protected void punchHoleFor(Address member)
```
  - closeHoleFor
```
protected void closeHoleFor(Address member)
```
  - determineCoordinator
```
protected Address determineCoordinator()
```
    Return the first element of members which is not me. Otherwise return null.
  - handleViewChange
```
protected void handleViewChange(View v)
```
  - handleException
```
protected void handleException(java.lang.Throwable exception)
```
  - handle
```
public void handle(Address state_requester)
```
    指定者:
    
    handle 在接口中 ProcessingQueue.Handler<Address>
  - handleStateReq
```
protected void handleStateReq(Address requester)
```
  - getStateFromApplication
```
protected void getStateFromApplication(Address requester,
                           Digest digest)
```
  - sendException
```
protected void sendException(Address requester,
                 java.lang.Throwable exception)
```
  - handleStateRsp
```
protected void handleStateRsp(Digest digest,
                  Address sender,
                  byte[] state)
```
    Set the digest and the send the state up to the application

类 STATE_TRANSFER

嵌套类概要

字段概要

从类继承的字段 com.fr.third.jgroups.stack.Protocol

构造器概要

方法概要

从类继承的方法 com.fr.third.jgroups.stack.Protocol

从类继承的方法 java.lang.Object

字段详细资料

start

stop

num_state_reqs

num_bytes_sent

avg_state_size

local_addr

view

members

state_requesters

waiting_for_state_response

flushProtocolInStack

构造器详细资料

STATE_TRANSFER

方法详细资料

getNumberOfStateRequests

getNumberOfStateBytesSent

getAverageStateSize

requiredDownServices

resetStats

init

start

stop

closeBarrierAndSuspendStable

openBarrierAndResumeStable

openBarrier

resumeStable

up

down

isDigestNeeded

punchHoleFor

closeHoleFor

determineCoordinator

handleViewChange

handleException

handle

handleStateReq

getStateFromApplication

sendException

handleStateRsp