Package org.postgresql.replication

Class LogSequenceNumber

  • All Implemented Interfaces:
    java.lang.Comparable<LogSequenceNumber>
    public final class LogSequenceNumber
extends java.lang.Object
implements java.lang.Comparable<LogSequenceNumber>
    LSN (Log Sequence Number) data which is a pointer to a location in the XLOG.

    • Field Detail

      • INVALID_LSN

        public static final LogSequenceNumber INVALID_LSN
        Zero is used indicate an invalid pointer. Bootstrap skips the first possible WAL segment, initializing the first WAL page at XLOG_SEG_SIZE, so no XLOG record can begin at zero.

      • value

        private final long value

    • Constructor Detail

      • LogSequenceNumber

        private LogSequenceNumber​(long value)

    • Method Detail

      • valueOf

        public static LogSequenceNumber valueOf​(long value)
        Parameters:
        value - numeric represent position in the write-ahead log stream
        Returns:
        not null LSN instance

      • valueOf

        public static LogSequenceNumber valueOf​(java.lang.String strValue)
        Create LSN instance by string represent LSN.
        Parameters:
        strValue - not null string as two hexadecimal numbers of up to 8 digits each, separated by a slash. For example 16/3002D50, 0/15D68C50
        Returns:
        not null LSN instance where if specified string represent have not valid form INVALID_LSN

      • asLong

        public long asLong()
        Returns:
        Long represent position in the write-ahead log stream

      • asString

        public java.lang.String asString()
        Returns:
        String represent position in the write-ahead log stream as two hexadecimal numbers of up to 8 digits each, separated by a slash. For example 16/3002D50, 0/15D68C50

      • equals

        public boolean equals​(java.lang.Object o)
        Overrides:
        equals in class java.lang.Object

      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class java.lang.Object

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object