Package org.h2.mvstore

Class MVStoreTool

  • public class MVStoreTool
extends java.lang.Object
    Utility methods used in combination with the MVStore.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      private static class  MVStoreTool.GenericDataType
      A data type that can read any data that is persisted, and converts it to a byte array.

    • Constructor Summary

      Constructors 
      Constructor Description
      MVStoreTool()  

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static void compact​(java.lang.String fileName, boolean compress)
      Compress the store by creating a new file and copying the live pages there.
      static void compact​(java.lang.String sourceFileName, java.lang.String targetFileName, boolean compress)
      Copy all live pages from the source store to the target store.
      static void compact​(MVStore source, MVStore target)
      Copy all live pages from the source store to the target store.
      static void compactCleanUp​(java.lang.String fileName)
      Clean up if needed, in a case a compact operation was interrupted due to killing the process or a power failure.
      static void dump​(java.lang.String fileName, boolean details)
      Read the contents of the file and write them to system out.
      static void dump​(java.lang.String fileName, java.io.Writer writer, boolean details)
      Read the contents of the file and display them in a human-readable format.
      private static java.lang.String formatTimestamp​(long t, long start)  
      private static Compressor getCompressor​(boolean fast)  
      (package private) static MVMap.Builder<java.lang.Object,​java.lang.Object> getGenericMapBuilder()  
      private static int getPercent​(long value, long max)  
      static void info​(java.lang.String fileName)
      Read the summary information of the file and write them to system out.
      static java.lang.String info​(java.lang.String fileName, java.io.Writer writer)
      Read the summary information of the file and write them to system out.
      static void main​(java.lang.String... args)
      Runs this tool.
      static void repair​(java.lang.String fileName)
      Repair a store by rolling back to the newest good version.
      static long rollback​(java.lang.String fileName, long targetVersion, java.io.Writer writer)
      Roll back to a given revision into a file called *.temp.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • MVStoreTool

        public MVStoreTool()

    • Method Detail

      • main

        public static void main​(java.lang.String... args)
        Runs this tool. Options are case sensitive. Supported options are:
        Command line options
        [-dump <fileName>] Dump the contends of the file
        [-info <fileName>] Get summary information about a file
        [-compact <fileName>] Compact a store
        [-compress <fileName>] Compact a store with compression enabled
        Parameters:
        args - the command line arguments

      • dump

        public static void dump​(java.lang.String fileName,
                        boolean details)
        Read the contents of the file and write them to system out.
        Parameters:
        fileName - the name of the file
        details - whether to print details

      • info

        public static void info​(java.lang.String fileName)
        Read the summary information of the file and write them to system out.
        Parameters:
        fileName - the name of the file

      • dump

        public static void dump​(java.lang.String fileName,
                        java.io.Writer writer,
                        boolean details)
        Read the contents of the file and display them in a human-readable format.
        Parameters:
        fileName - the name of the file
        writer - the print writer
        details - print the page details

      • getCompressor

        private static Compressor getCompressor​(boolean fast)

      • info

        public static java.lang.String info​(java.lang.String fileName,
                                    java.io.Writer writer)
        Read the summary information of the file and write them to system out.
        Parameters:
        fileName - the name of the file
        writer - the print writer
        Returns:
        null if successful (if there was no error), otherwise the error message

      • formatTimestamp

        private static java.lang.String formatTimestamp​(long t,
                                                long start)

      • getPercent

        private static int getPercent​(long value,
                              long max)

      • compact

        public static void compact​(java.lang.String fileName,
                           boolean compress)
        Compress the store by creating a new file and copying the live pages there. Temporarily, a file with the suffix ".tempFile" is created. This file is then renamed, replacing the original file, if possible. If not, the new file is renamed to ".newFile", then the old file is removed, and the new file is renamed. This might be interrupted, so it's better to compactCleanUp before opening a store, in case this method was used.
        Parameters:
        fileName - the file name
        compress - whether to compress the data

      • compactCleanUp

        public static void compactCleanUp​(java.lang.String fileName)
        Clean up if needed, in a case a compact operation was interrupted due to killing the process or a power failure. This will delete temporary files (if any), and in case atomic file replacements were not used, rename the new file.
        Parameters:
        fileName - the file name

      • compact

        public static void compact​(java.lang.String sourceFileName,
                           java.lang.String targetFileName,
                           boolean compress)
        Copy all live pages from the source store to the target store.
        Parameters:
        sourceFileName - the name of the source store
        targetFileName - the name of the target store
        compress - whether to compress the data

      • compact

        public static void compact​(MVStore source,
                           MVStore target)
        Copy all live pages from the source store to the target store.
        Parameters:
        source - the source store
        target - the target store

      • repair

        public static void repair​(java.lang.String fileName)
        Repair a store by rolling back to the newest good version.
        Parameters:
        fileName - the file name

      • rollback

        public static long rollback​(java.lang.String fileName,
                            long targetVersion,
                            java.io.Writer writer)
        Roll back to a given revision into a file called *.temp.
        Parameters:
        fileName - the file name
        targetVersion - the version to roll back to (Long.MAX_VALUE for the latest version)
        writer - the log writer
        Returns:
        the version rolled back to (-1 if no version)

      • getGenericMapBuilder

        static MVMap.Builder<java.lang.Object,​java.lang.Object> getGenericMapBuilder()