java.lang.Object
org.rrd4j.core.RrdPrimitive<U>
org.rrd4j.core.RrdDouble<U>
Type Parameters:
U - the updater type
class RrdDouble<U extends RrdUpdater<U>>extends RrdPrimitive<U>
RRD double primitive type.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private double
    cache
    Value read from or written to the file.
    private boolean
    cached
    True while the value is held in memory.

    Fields inherited from class RrdPrimitive

    RRD_DOUBLE, RRD_INT, RRD_LONG, RRD_PRIM_SIZES, RRD_STRING, STRING_LENGTH
    Modifier and Type
    Field
    Description
    (package private) static final int
    RRD_DOUBLE
    Type identifier for double RRD primitives.
    (package private) static final int
    RRD_INT
    Type identifier for integer RRD primitives.
    (package private) static final int
    RRD_LONG
    Type identifier for long RRD primitives.
    (package private) static final int[]
    RRD_PRIM_SIZES
    Array containing the size in bytes for each RRD primitive type.
    (package private) static final int
    RRD_STRING
    Type identifier for string RRD primitives.
    (package private) static final int
    STRING_LENGTH
    Maximum length of string values stored in RRD primitives.

  • Constructor Summary

    Constructors
    Constructor
    Description
    RrdDouble(RrdUpdater<U> updater)
    Create a double primitive that is not flagged as constant.
    RrdDouble(RrdUpdater<U> updater, boolean isConstant)
    Create a double primitive, optionally flagged as constant.

  • Method Summary

    All Methods
    Modifier and Type
    Method
    Description
    (package private) double
    get()
    Retrieve the stored double value.
    (package private) void
    set(double value)
    Store a double value with optional caching.

    Methods inherited from class RrdPrimitive

    isCachingAllowed, readBytes, readDouble, readDouble, readDouble, readEnum, readInt, readLong, readString, writeBytes, writeDouble, writeDouble, writeDouble, writeDouble, writeEnum, writeInt, writeLong, writeString
    Modifier and Type
    Method
    Description
    (package private) final boolean
    isCachingAllowed()
    Checks if caching is allowed for this primitive.
    (package private) final byte[]
    readBytes()
    Raw byte array from backend storage.
    (package private) final double
    readDouble()
    Reads the double value from backend storage.
    (package private) final double
    readDouble(int index)
    Position in the primitive array.
    (package private) final double[]
    readDouble(int index, int count)
    Starting position in the primitive array.
    protected final <E extends Enum<E>>
    E
    readEnum(Class<E> clazz)
    Deserialize an enum value from backend storage.
    (package private) final int
    readInt()
    Reads the int value from backend storage.
    (package private) final long
    readLong()
    Reads the long value from backend storage.
    (package private) final String
    readString()
    Reads the string value from backend storage.
    (package private) final void
    writeBytes(byte[] b)
    Byte array to write to backend storage.
    (package private) final void
    writeDouble(double value)
    Double value to write to backend storage.
    (package private) final void
    writeDouble(int index, double value)
    Position in the primitive array.
    (package private) final void
    writeDouble(int index, double[] values)
    Starting position in the primitive array.
    (package private) final void
    writeDouble(int index, double value, int count)
    Starting position in the primitive array.
    protected final <E extends Enum<E>>
    void
    writeEnum(E value)
    Serialize an enum value to backend storage.
    (package private) final void
    writeInt(int value)
    Int value to write to backend storage.
    (package private) final void
    writeLong(long value)
    Long value to write to backend storage.
    (package private) final void
    writeString(String value)
    String value to write to backend storage.

    Methods inherited from class Object

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

  • Field Details

    • cache

      private double cache
      Value read from or written to the file.

    • cached

      private boolean cached
      True while the value is held in memory.

  • Constructor Details

    • RrdDouble

      RrdDouble(RrdUpdater<U> updater, boolean isConstant)
      Create a double primitive, optionally flagged as constant.
      Parameters:
      updater - the updater that owns this primitive
      isConstant - true to mark the value as constant, so the backend may skip storing it

    • RrdDouble

      RrdDouble(RrdUpdater<U> updater)
      Create a double primitive that is not flagged as constant.
      Parameters:
      updater - the updater that owns this primitive

  • Method Details

    • set

      void set(double value) throws IOException
      Store a double value with optional caching.
      Parameters:
      value - the value to set
      Throws:
      IOException - if an I/O error occurs

    • get

      double get() throws IOException
      Retrieve the stored double value.
      Returns:
      the stored double
      Throws:
      IOException - if an I/O error occurs