Package org.jcsp.util
Class Buffer
- java.lang.Object
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- org.jcsp.util.Buffer
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- All Implemented Interfaces:
java.io.Serializable
,java.lang.Cloneable
,ChannelDataStore
public class Buffer extends java.lang.Object implements ChannelDataStore, java.io.Serializable
This is used to create a buffered object channel that never loses data.Description
Buffer is an implementation of ChannelDataStore that yields a blocking FIFO buffered semantics for a channel. See the static construction methods ofChannel
(Channel.one2one(org.jcsp.util.ChannelDataStore)
etc.).The getState method returns EMPTY, NONEMPTYFULL or FULL according to the state of the buffer.
- Author:
- P.D. Austin
- See Also:
ZeroBuffer
,OverWriteOldestBuffer
,OverWritingBuffer
,OverFlowingBuffer
,InfiniteBuffer
,Channel
, Serialized Form
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Field Summary
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Fields inherited from interface org.jcsp.util.ChannelDataStore
EMPTY, FULL, NONEMPTYFULL
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Constructor Summary
Constructors Constructor Description Buffer(int size)
Construct a new Buffer with the specified size.
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description java.lang.Object
clone()
Returns a new (and EMPTY) Buffer with the same creation parameters as this one.void
endGet()
Removes the oldest object from the buffer.java.lang.Object
get()
Returns the oldest Object from the Buffer and removes it.int
getState()
Returns the current state of the Buffer.void
put(java.lang.Object value)
Puts a new Object into the Buffer.void
removeAll()
Deletes all items in the buffer, leaving it empty.java.lang.Object
startGet()
Returns the oldest object from the buffer but does not remove it.
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Constructor Detail
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Buffer
public Buffer(int size)
Construct a new Buffer with the specified size.- Parameters:
size
- the number of Objects the Buffer can store.- Throws:
BufferSizeError
- if size is negative. Note: no action should be taken to try/catch this exception - application code generating it is in error and needs correcting.
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Method Detail
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get
public java.lang.Object get()
Returns the oldest Object from the Buffer and removes it.Pre-condition: getState must not currently return EMPTY.
- Specified by:
get
in interfaceChannelDataStore
- Returns:
- the oldest Object from the Buffer
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startGet
public java.lang.Object startGet()
Returns the oldest object from the buffer but does not remove it. Pre-condition: getState must not currently return EMPTY.- Specified by:
startGet
in interfaceChannelDataStore
- Returns:
- the oldest Object from the Buffer
- See Also:
ChannelDataStore.endGet()
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endGet
public void endGet()
Removes the oldest object from the buffer.- Specified by:
endGet
in interfaceChannelDataStore
- See Also:
ChannelDataStore.startGet()
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put
public void put(java.lang.Object value)
Puts a new Object into the Buffer.Pre-condition: getState must not currently return FULL.
- Specified by:
put
in interfaceChannelDataStore
- Parameters:
value
- the Object to put into the Buffer
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getState
public int getState()
Returns the current state of the Buffer.- Specified by:
getState
in interfaceChannelDataStore
- Returns:
- the current state of the Buffer (EMPTY, NONEMPTYFULL or FULL)
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clone
public java.lang.Object clone()
Returns a new (and EMPTY) Buffer with the same creation parameters as this one.Note: Only the size and structure of the Buffer is cloned, not any stored data.
- Specified by:
clone
in interfaceChannelDataStore
- Overrides:
clone
in classjava.lang.Object
- Returns:
- the cloned instance of this Buffer
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removeAll
public void removeAll()
Description copied from interface:ChannelDataStore
Deletes all items in the buffer, leaving it empty.- Specified by:
removeAll
in interfaceChannelDataStore
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