Package com.helger.base.compare

Class CompareHelper

java.lang.Object
com.helger.base.compare.CompareHelper
@Immutable public class CompareHelper extends Object
A small helper class that provides comparison methods that are null safe. Also provides secure ways to compare double and float values.
Author:
Philip Helger

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final boolean
    DEFAULT_NULL_VALUES_COME_FIRST
    By default null values come first

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    CompareHelper()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static int
    compare(byte n1, byte n2)
    Special version for byte
    static int
    compare(char n1, char n2)
    Special version for byte
    static int
    compare(double d1, double d2)
    Special version for doubles
    static int
    compare(float f1, float f2)
    Special version for floats
    static int
    compare(int n1, int n2)
    Special version for int
    static int
    compare(long n1, long n2)
    Special version for long
    static int
    compare(short n1, short n2)
    Special version for short
    static <DATATYPE extends Comparable<? super DATATYPE>>
    int
    compare(@Nullable DATATYPE aObj1, @Nullable DATATYPE aObj2)
    Compare the passed items and handle null values correctly.
    static <DATATYPE extends Comparable<? super DATATYPE>>
    int
    compare(@Nullable DATATYPE aObj1, @Nullable DATATYPE aObj2, boolean bNullValuesComeFirst)
    Compare the passed items and handle null values correctly.
    static <DATATYPE> int
    compare(@Nullable DATATYPE aObj1, @Nullable DATATYPE aObj2, @NonNull Comparator<? super DATATYPE> aComp)
    Compare the passed items and handle null values correctly.
    static <DATATYPE> int
    compare(@Nullable DATATYPE aObj1, @Nullable DATATYPE aObj2, @NonNull Comparator<? super DATATYPE> aComp, boolean bNullValuesComeFirst)
    Compare the passed items and handle null values correctly.
    static int
    compare(@Nullable String sStr1, @Nullable String sStr2, @NonNull Collator aCollator)
    Compare the passed strings using the specified Collator and handle null values correctly.
    static int
    compare(@Nullable String sStr1, @Nullable String sStr2, @NonNull Collator aCollator, boolean bNullValuesComeFirst)
    Compare the passed strings using the specified Collator and handle null values correctly.
    static int
    compareFalseBeforeTrue(boolean b1, boolean b2)
    Special version for boolean, true before false
    static int
    compareIgnoreCase(@Nullable String sStr1, @Nullable String sStr2)
    Compare the passed strings case insensitive and handle null values correctly.
    static int
    compareIgnoreCase(@Nullable String sStr1, @Nullable String sStr2, boolean bNullValuesComeFirst)
    Compare the passed strings case insensitive and handle null values correctly.
    static int
    compareTrueBeforeFalse(boolean b1, boolean b2)
    Special version for boolean, true before false

    Methods inherited from class java.lang.Object

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

  • Field Details

    • DEFAULT_NULL_VALUES_COME_FIRST

      public static final boolean DEFAULT_NULL_VALUES_COME_FIRST
      By default null values come first
      See Also:

  • Constructor Details

    • CompareHelper

      protected CompareHelper()

  • Method Details

    • compareTrueBeforeFalse

      public static int compareTrueBeforeFalse(boolean b1, boolean b2)
      Special version for boolean, true before false
      Parameters:
      b1 - First value
      b2 - Second value
      Returns:
      -1, 0 or + 1

    • compareFalseBeforeTrue

      public static int compareFalseBeforeTrue(boolean b1, boolean b2)
      Special version for boolean, true before false
      Parameters:
      b1 - First value
      b2 - Second value
      Returns:
      -1, 0 or + 1

    • compare

      public static int compare(byte n1, byte n2)
      Special version for byte
      Parameters:
      n1 - First value
      n2 - Second value
      Returns:
      value <0, 0 or >0.

    • compare

      public static int compare(char n1, char n2)
      Special version for byte
      Parameters:
      n1 - First value
      n2 - Second value
      Returns:
      value <0, 0 or >0.

    • compare

      public static int compare(double d1, double d2)
      Special version for doubles
      Parameters:
      d1 - First value
      d2 - Second value
      Returns:
      value <0, 0 or >0.

    • compare

      public static int compare(float f1, float f2)
      Special version for floats
      Parameters:
      f1 - First value
      f2 - Second value
      Returns:
      value <0, 0 or >0.

    • compare

      public static int compare(int n1, int n2)
      Special version for int
      Parameters:
      n1 - First value
      n2 - Second value
      Returns:
      value <0, 0 or >0.

    • compare

      public static int compare(long n1, long n2)
      Special version for long
      Parameters:
      n1 - First value
      n2 - Second value
      Returns:
      value <0, 0 or >0.

    • compare

      public static int compare(short n1, short n2)
      Special version for short
      Parameters:
      n1 - First value
      n2 - Second value
      Returns:
      value <0, 0 or >0.

    • compare

      public static <DATATYPE extends Comparable<? super DATATYPE>> int compare(@Nullable DATATYPE aObj1, @Nullable DATATYPE aObj2)
      Compare the passed items and handle null values correctly. A null value is always smaller than a non-null value.
      Type Parameters:
      DATATYPE - Any comparable object to be used. Both need to be of the same type.
      Parameters:
      aObj1 - First object to compare. May be null.
      aObj2 - Second object to compare. May be null.
      Returns:
      0 if they are equal (or both null), -1 or +1.

    • compare

      public static <DATATYPE extends Comparable<? super DATATYPE>> int compare(@Nullable DATATYPE aObj1, @Nullable DATATYPE aObj2, boolean bNullValuesComeFirst)
      Compare the passed items and handle null values correctly. A null value is always smaller than a non-null value.
      Type Parameters:
      DATATYPE - Any comparable object to be used. Both need to be of the same type.
      Parameters:
      aObj1 - First object to compare. May be null.
      aObj2 - Second object to compare. May be null.
      bNullValuesComeFirst - if true null values are ordered before non-null values
      Returns:
      0 if they are equal (or both null), -1 or +1.

    • compare

      public static <DATATYPE> int compare(@Nullable DATATYPE aObj1, @Nullable DATATYPE aObj2, @NonNull Comparator<? super DATATYPE> aComp)
      Compare the passed items and handle null values correctly. A null value is always smaller than a non-null value.
      Type Parameters:
      DATATYPE - Any object to be used. Both need to be of the same type.
      Parameters:
      aObj1 - First object to compare. May be null.
      aObj2 - Second object to compare. May be null.
      aComp - The comparator to be used if both parameters are not null. The comparator itself may not be null.
      Returns:
      0 if they are equal (or both null), -1 or +1.

    • compare

      public static <DATATYPE> int compare(@Nullable DATATYPE aObj1, @Nullable DATATYPE aObj2, @NonNull Comparator<? super DATATYPE> aComp, boolean bNullValuesComeFirst)
      Compare the passed items and handle null values correctly. A null value is always smaller than a non-null value.
      Type Parameters:
      DATATYPE - Any object to be used. Both need to be of the same type.
      Parameters:
      aObj1 - First object to compare. May be null.
      aObj2 - Second object to compare. May be null.
      aComp - The comparator to be used if both parameters are not null. The comparator itself may not be null.
      bNullValuesComeFirst - if true null values are ordered before non-null values
      Returns:
      0 if they are equal (or both null), -1 or +1.

    • compare

      public static int compare(@Nullable String sStr1, @Nullable String sStr2, @NonNull Collator aCollator)
      Compare the passed strings using the specified Collator and handle null values correctly. A null value is always smaller than a non-null value.
      Parameters:
      sStr1 - First string to compare. May be null.
      sStr2 - Second string to compare. May be null.
      aCollator - The collator to use for comparison. May not be null.
      Returns:
      0 if they are equal (or both null), -1 or +1.

    • compare

      public static int compare(@Nullable String sStr1, @Nullable String sStr2, @NonNull Collator aCollator, boolean bNullValuesComeFirst)
      Compare the passed strings using the specified Collator and handle null values correctly.
      Parameters:
      sStr1 - First string to compare. May be null.
      sStr2 - Second string to compare. May be null.
      aCollator - The collator to use for comparison. May not be null.
      bNullValuesComeFirst - if true null values are ordered before non-null values
      Returns:
      0 if they are equal (or both null), -1 or +1.

    • compareIgnoreCase

      public static int compareIgnoreCase(@Nullable String sStr1, @Nullable String sStr2)
      Compare the passed strings case insensitive and handle null values correctly. A null value is always smaller than a non-null value.
      Parameters:
      sStr1 - First string to compare. May be null.
      sStr2 - Second string to compare. May be null.
      Returns:
      0 if they are equal (or both null), -1 or +1.

    • compareIgnoreCase

      public static int compareIgnoreCase(@Nullable String sStr1, @Nullable String sStr2, boolean bNullValuesComeFirst)
      Compare the passed strings case insensitive and handle null values correctly.
      Parameters:
      sStr1 - First string to compare. May be null.
      sStr2 - Second string to compare. May be null.
      bNullValuesComeFirst - if true null values are ordered before non-null values
      Returns:
      0 if they are equal (or both null), -1 or +1.