Apache Derby Database Engine and Embedded JDBC Driver 10.17.1.0 · org.apache.derby.impl.store.raw.log.LogCounter

Modifier and Type	Field and Description
public static final long	DERBY_10_0_MAX_LOGFILE_NUMBER
private static final long	FILE_NUMBER_SHIFT
private static final long	FILE_POSITION_MASK
private long	fileNumber
private long	filePosition
public static final long	INVALID_LOG_INSTANT Hides org.apache.derby.iapi.store.raw.log.LogInstant.INVALID_LOG_INSTANT. A well defined value of an invalid log instant.
public static final long	MAX_LOGFILE_NUMBER
public static final long	MAX_LOGFILE_SIZE

Access	Constructor and Description
public	LogCounter(long value)
public	LogCounter(long fileNumber, long position)
public	LogCounter() Public niladic constructor needed for Formatable interface.

Method Summary

Modifier and Type	Method and Description
public boolean	equals(Object a DatabaseInstant from the same database as this. other) Overrides java.lang.Object.equals. Implements org.apache.derby.iapi.store.access.DatabaseInstant.equals. Return true if this DatabaseInstant equals DatabaseInstant from the same database.
public static final long	getLogFileNumber(long valueAsLong)
public long	getLogFileNumber()
public static final long	getLogFilePosition(long valueAsLong)
public long	getLogFilePosition()
public int	Returns: the formatID of this class getTypeFormatId() Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId. Get the formatID which corresponds to this class.
public long	getValueAsLong() These following methods are only intended to be called by an implementation of a log factory.
public int	hashCode() Overrides java.lang.Object.hashCode. Returns a hash code value for this object.
public boolean	lessThan(DatabaseInstant a DatabaseInstant from the same database as this. other) Implements org.apache.derby.iapi.store.access.DatabaseInstant.lessThan. LogScan methods
public static final long	makeLogInstantAsLong(long filenum, long filepos) Static functions that can only be used inside the RawStore's log factory which passes the log counter around encoded as a long
public DatabaseInstant	next() Implements org.apache.derby.iapi.store.access.DatabaseInstant.next. Return the next higher DatabaseInstant.
public DatabaseInstant	prior() Implements org.apache.derby.iapi.store.access.DatabaseInstant.prior. Return the next lower DatabaseInstant.
public void	readExternal(ObjectInput the stream to read data from in order to restore the object oi) Implements java.io.Externalizable.readExternal. Read this in.
public static String	toDebugString(long instant)
public String	toString() Overrides java.lang.Object.toString. Implements org.apache.derby.iapi.store.access.DatabaseInstant.toString. Convert the database instant to a string.
public void	writeExternal(ObjectOutput the stream to write the object to oo) Implements java.io.Externalizable.writeExternal. Write this out.

Inherited from java.lang.Object:: clone finalize getClass notify notifyAll wait wait wait

DERBY_10_0_MAX_LOGFILE_NUMBER	back to summary
public static final long DERBY_10_0_MAX_LOGFILE_NUMBER

FILE_NUMBER_SHIFT	back to summary
private static final long FILE_NUMBER_SHIFT

FILE_POSITION_MASK	back to summary
private static final long FILE_POSITION_MASK

fileNumber	back to summary
private long fileNumber

filePosition	back to summary
private long filePosition

INVALID_LOG_INSTANT	back to summary
public static final long INVALID_LOG_INSTANT Hides org.apache.derby.iapi.store.raw.log.LogInstant.INVALID_LOG_INSTANT. A well defined value of an invalid log instant.

MAX_LOGFILE_NUMBER	back to summary
public static final long MAX_LOGFILE_NUMBER

MAX_LOGFILE_SIZE	back to summary
public static final long MAX_LOGFILE_SIZE

LogCounter	back to summary
public LogCounter(long value)

LogCounter	back to summary
public LogCounter(long fileNumber, long position)

LogCounter	back to summary
public LogCounter() Public niladic constructor needed for Formatable interface.

Method Detail

equals	back to summary
public boolean equals(Object other) Overrides java.lang.Object.equals. Implements org.apache.derby.iapi.store.access.DatabaseInstant.equals. Doc from org.apache.derby.iapi.store.access.DatabaseInstant.equals. Return true if this DatabaseInstant equals DatabaseInstant from the same database. Parameters other:Object a DatabaseInstant from the same database as this. Returns:boolean the comparison result. If 'other' is from another database the result is undefined.

equals

back to summary

public boolean equals(Object other)

Overrides java.lang.Object.equals.

Implements org.apache.derby.iapi.store.access.DatabaseInstant.equals.

Doc from org.apache.derby.iapi.store.access.DatabaseInstant.equals.

Return true if this DatabaseInstant equals DatabaseInstant from the same database.

Parameters

other:Object: a DatabaseInstant from the same database as this.

Returns:boolean

the comparison result. If 'other' is from another database the result is undefined.

getLogFileNumber	back to summary
public static final long getLogFileNumber(long valueAsLong)

getLogFileNumber	back to summary
public long getLogFileNumber()

getLogFilePosition	back to summary
public static final long getLogFilePosition(long valueAsLong)

getLogFilePosition	back to summary
public long getLogFilePosition()

getTypeFormatId	back to summary
public int getTypeFormatId() Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId. Get the formatID which corresponds to this class. Returns:int the formatID of this class

getTypeFormatId

back to summary

public int getTypeFormatId()

Implements org.apache.derby.iapi.services.io.TypedFormat.getTypeFormatId.

Get the formatID which corresponds to this class.

Returns:int: the formatID of this class

getValueAsLong	back to summary
public long getValueAsLong() These following methods are only intended to be called by an implementation of a log factory. All other uses of this object should only see it as a log instant.

hashCode back to summary

hashCode	back to summary
public int hashCode() Overrides java.lang.Object.hashCode. Doc from java.lang.Object.hashCode. Returns a hash code value for this object. This method is supported for the benefit of hash tables such as those provided by `java.util.HashMap`. The general contract of `hashCode` is: Whenever it is invoked on the same object more than once during an execution of a Java application, the `hashCode` method must consistently return the same integer, provided no information used in `equals` comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. If two objects are equal according to the `equals` method, then calling the `hashCode` method on each of the two objects must produce the same integer result. It is not required that if two objects are unequal according to the `equals` method, then calling the `hashCode` method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables. Returns:int a hash code value for this object

public int hashCode()

Overrides java.lang.Object.hashCode.

Doc from java.lang.Object.hashCode.

Returns a hash code value for this object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.

The general contract of hashCode is:

Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.

Returns:int: a hash code value for this object

lessThan	back to summary
public boolean lessThan(DatabaseInstant other) Implements org.apache.derby.iapi.store.access.DatabaseInstant.lessThan. LogScan methods Parameters other:DatabaseInstant Doc from org.apache.derby.iapi.store.access.DatabaseInstant.lessThan. a DatabaseInstant from the same database as this. Returns:boolean Doc from org.apache.derby.iapi.store.access.DatabaseInstant.lessThan. the comparison result. If 'other' is from another database the result is undefined.

lessThan

back to summary

public boolean lessThan(DatabaseInstant other)

Implements org.apache.derby.iapi.store.access.DatabaseInstant.lessThan.

LogScan methods

Parameters

other:DatabaseInstant

Doc from org.apache.derby.iapi.store.access.DatabaseInstant.lessThan.

a DatabaseInstant from the same database as this.

Returns:boolean

Doc from org.apache.derby.iapi.store.access.DatabaseInstant.lessThan.

the comparison result. If 'other' is from another database the result is undefined.

makeLogInstantAsLong	back to summary
public static final long makeLogInstantAsLong(long filenum, long filepos) Static functions that can only be used inside the RawStore's log factory which passes the log counter around encoded as a long

next	back to summary
public DatabaseInstant next() Implements org.apache.derby.iapi.store.access.DatabaseInstant.next. Doc from org.apache.derby.iapi.store.access.DatabaseInstant.next. Return the next higher DatabaseInstant. There is no requirement that a transaction with the next instant exist in the database. It is required that this.lessThan( this.next()), and that no instant can be between this and this.next(). If the DatabaseInstant is implemented using a integer then next() should return a new DatabaseInstant formed by adding one to the integer. Returns:DatabaseInstant the next possible DatabaseInstant

back to summary

public DatabaseInstant next()

Implements org.apache.derby.iapi.store.access.DatabaseInstant.next.

Doc from org.apache.derby.iapi.store.access.DatabaseInstant.next.

Return the next higher DatabaseInstant. There is no requirement that a transaction with the next instant exist in the database. It is required that this.lessThan( this.next()), and that no instant can be between this and this.next(). If the DatabaseInstant is implemented using a integer then next() should return a new DatabaseInstant formed by adding one to the integer.

Returns:DatabaseInstant: the next possible DatabaseInstant

prior	back to summary
public DatabaseInstant prior() Implements org.apache.derby.iapi.store.access.DatabaseInstant.prior. Doc from org.apache.derby.iapi.store.access.DatabaseInstant.prior. Return the next lower DatabaseInstant. There is no requirement that a transaction with the next instant exist in the database. It is required that this.prior().lessThan( this), and that no instant can be between this and this.prior(). If the DatabaseInstant is implemented using a integer then prior() should return a new DatabaseInstant formed by subtracting one from the integer. Returns:DatabaseInstant the prior possible DatabaseInstant

prior

back to summary

public DatabaseInstant prior()

Implements org.apache.derby.iapi.store.access.DatabaseInstant.prior.

Doc from org.apache.derby.iapi.store.access.DatabaseInstant.prior.

Return the next lower DatabaseInstant. There is no requirement that a transaction with the next instant exist in the database. It is required that this.prior().lessThan( this), and that no instant can be between this and this.prior(). If the DatabaseInstant is implemented using a integer then prior() should return a new DatabaseInstant formed by subtracting one from the integer.

Returns:DatabaseInstant: the prior possible DatabaseInstant

readExternal	back to summary
public void readExternal(ObjectInput oi) throws IOException, ClassNotFoundException Implements java.io.Externalizable.readExternal. Read this in. Parameters oi:ObjectInput Doc from java.io.Externalizable.readExternal. the stream to read data from in order to restore the object Exceptions IOException: error reading from log stream ClassNotFoundException: corrupted log stream

readExternal

back to summary

public void readExternal(ObjectInput oi) throws IOException, ClassNotFoundException

Implements java.io.Externalizable.readExternal.

Read this in.

Parameters

oi:ObjectInput

Doc from java.io.Externalizable.readExternal.

the stream to read data from in order to restore the object

Exceptions

IOException:: error reading from log stream
ClassNotFoundException:: corrupted log stream

toDebugString	back to summary
public static String toDebugString(long instant)

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Implements org.apache.derby.iapi.store.access.DatabaseInstant.toString. Doc from org.apache.derby.iapi.store.access.DatabaseInstant.toString. Convert the database instant to a string. This is mainly used for debugging. Returns:String a string representation of the instant.

toString

back to summary

public String toString()

Overrides java.lang.Object.toString.

Implements org.apache.derby.iapi.store.access.DatabaseInstant.toString.

Doc from org.apache.derby.iapi.store.access.DatabaseInstant.toString.

Convert the database instant to a string. This is mainly used for debugging.

Returns:String: a string representation of the instant.

writeExternal	back to summary
public void writeExternal(ObjectOutput oo) throws IOException Implements java.io.Externalizable.writeExternal. Write this out. Parameters oo:ObjectOutput Doc from java.io.Externalizable.writeExternal. the stream to write the object to Exceptions IOException: error writing to log stream

writeExternal

back to summary

public void writeExternal(ObjectOutput oo) throws IOException

Implements java.io.Externalizable.writeExternal.

Write this out.

Parameters

oo:ObjectOutput

Doc from java.io.Externalizable.writeExternal.

the stream to write the object to

Exceptions

IOException:: error writing to log stream

public Class LogCounter

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Constructor Summary

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Field Detail

Constructor Detail

Method Detail