Package io.objectbox.query

Class PropertyQuery

java.lang.Object
io.objectbox.query.PropertyQuery
public class PropertyQuery extends Object
Query for a specific property; create using Query.property(Property). Note: Property values do currently not consider any order defined for the main Query object (subject to change in a future version).

  • Method Summary

    Modifier and Type
    Method
    Description
    double
    avg()
    Calculates the average of all values for the given number property over all Objects matching the query.
    long
    avgLong()
    Calculates the average of all values for the given integer property over all Objects matching the query.
    long
    count()
    The count of non-null values.
    PropertyQuery
    distinct()
    Only distinct values should be returned (e.g.
    PropertyQuery
    distinct(QueryBuilder.StringOrder stringOrder)
    For string properties you can specify QueryBuilder.StringOrder.CASE_SENSITIVE if you want to have case sensitive distinct values (e.g.
    Boolean
    findBoolean()
     
    Byte
    findByte()
     
    byte[]
    findBytes()
    Find the values for the given byte property for objects matching the query.
    Character
    findChar()
     
    char[]
    findChars()
    Find the values for the given int property for objects matching the query.
    Double
    findDouble()
     
    double[]
    findDoubles()
    Find the values for the given int property for objects matching the query.
    Float
    findFloat()
     
    float[]
    findFloats()
    Find the values for the given int property for objects matching the query.
    Integer
    findInt()
     
    int[]
    findInts()
    Find the values for the given int property for objects matching the query.
    Long
    findLong()
     
    long[]
    findLongs()
    Find the values for the given long property for objects matching the query.
    Short
    findShort()
     
    short[]
    findShorts()
    Find the values for the given int property for objects matching the query.
    String
    findString()
     
    String[]
    findStrings()
    Find the values for the given string property for objects matching the query.
    long
    max()
    Finds the maximum value for the given property over all Objects matching the query.
    double
    maxDouble()
    Finds the maximum value for the given property over all Objects matching the query.
    long
    min()
    Finds the minimum value for the given property over all Objects matching the query.
    double
    minDouble()
    Finds the minimum value for the given property over all objects matching the query.
    PropertyQuery
    nullValue(Object nullValue)
    By default, null values are not returned by find methods (primitive arrays cannot contains nulls).
    PropertyQuery
    reset()
    Clears all values (e.g.
    long
    sum()
    Sums up all values for the given property over all Objects matching the query.
    double
    sumDouble()
    Sums up all values for the given property over all Objects matching the query.
    PropertyQuery
    unique()
    For find methods returning single values, e.g.

    Methods inherited from class java.lang.Object

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

  • Method Details

    • reset

      public PropertyQuery reset()
      Clears all values (e.g. distinct and null value).

    • distinct

      public PropertyQuery distinct()
      Only distinct values should be returned (e.g. 1,2,3 instead of 1,1,2,3,3,3).

      Note: strings default to case-insensitive comparision; to change that call distinct(QueryBuilder.StringOrder).

    • distinct

      public PropertyQuery distinct(QueryBuilder.StringOrder stringOrder)
      For string properties you can specify QueryBuilder.StringOrder.CASE_SENSITIVE if you want to have case sensitive distinct values (e.g. returning "foo","Foo","FOO" instead of "foo").

    • unique

      public PropertyQuery unique()
      For find methods returning single values, e.g. findInt(), this will additional verify that the resulting value is unique. If there is any other resulting value resulting from this query, an exception will be thrown.

      Can be combined with distinct().

      Will be ignored for find methods returning multiple values, e.g. findInts().

    • nullValue

      public PropertyQuery nullValue(Object nullValue)
      By default, null values are not returned by find methods (primitive arrays cannot contains nulls). However, using this function, you can define an alternative value that will be returned for null values. E.g. -1 for ins/longs or "NULL" for strings.

    • findStrings

      public String[] findStrings()
      Find the values for the given string property for objects matching the query.

      Note: null values are excluded from results.

      Note: results are not guaranteed to be in any particular order.

      See also: distinct(), distinct(QueryBuilder.StringOrder)

      Returns:
      Found strings

    • findLongs

      public long[] findLongs()
      Find the values for the given long property for objects matching the query.

      Note: null values are excluded from results.

      Note: results are not guaranteed to be in any particular order.

      See also: distinct()

      Returns:
      Found longs

    • findInts

      public int[] findInts()
      Find the values for the given int property for objects matching the query.

      Note: null values are excluded from results.

      Note: results are not guaranteed to be in any particular order.

      See also: distinct()

    • findShorts

      public short[] findShorts()
      Find the values for the given int property for objects matching the query.

      Note: null values are excluded from results.

      Note: results are not guaranteed to be in any particular order.

      See also: distinct()

    • findChars

      public char[] findChars()
      Find the values for the given int property for objects matching the query.

      Note: null values are excluded from results.

      Note: results are not guaranteed to be in any particular order.

      See also: distinct()

    • findBytes

      public byte[] findBytes()
      Find the values for the given byte property for objects matching the query.

      Note: null values are excluded from results.

      Note: results are not guaranteed to be in any particular order.

    • findFloats

      public float[] findFloats()
      Find the values for the given int property for objects matching the query.

      Note: null values are excluded from results.

      Note: results are not guaranteed to be in any particular order.

      See also: distinct()

    • findDoubles

      public double[] findDoubles()
      Find the values for the given int property for objects matching the query.

      Note: null values are excluded from results.

      Note: results are not guaranteed to be in any particular order.

      See also: distinct()

    • findString

      public String findString()

    • findLong

      public Long findLong()

    • findInt

      public Integer findInt()

    • findShort

      public Short findShort()

    • findChar

      public Character findChar()

    • findByte

      public Byte findByte()

    • findBoolean

      public Boolean findBoolean()

    • findFloat

      public Float findFloat()

    • findDouble

      public Double findDouble()

    • sum

      public long sum()
      Sums up all values for the given property over all Objects matching the query.

      Note: this method is not recommended for properties of type long unless you know the contents of the DB not to overflow. Use sumDouble() instead if you cannot guarantee the sum to be in the long value range.

      Returns:
      0 in case no elements matched the query
      Throws:
      NumericOverflowException - if the sum exceeds the numbers Long can represent. This is different from Java arithmetic where it would "wrap around" (e.g. max. value + 1 = min. value).

    • sumDouble

      public double sumDouble()
      Sums up all values for the given property over all Objects matching the query.

      Note: for integer types int and smaller, sum() is usually preferred for sums.

      Returns:
      0 in case no elements matched the query

    • max

      public long max()
      Finds the maximum value for the given property over all Objects matching the query.
      Returns:
      Long.MIN_VALUE in case no elements matched the query

    • maxDouble

      public double maxDouble()
      Finds the maximum value for the given property over all Objects matching the query.
      Returns:
      NaN in case no elements matched the query

    • min

      public long min()
      Finds the minimum value for the given property over all Objects matching the query.
      Returns:
      Long.MAX_VALUE in case no elements matched the query

    • minDouble

      public double minDouble()
      Finds the minimum value for the given property over all objects matching the query.
      Returns:
      NaN in case no elements matched the query

    • avg

      public double avg()
      Calculates the average of all values for the given number property over all Objects matching the query.

      For integer properties you can also use avgLong().

      Returns:
      NaN in case no elements matched the query

    • avgLong

      public long avgLong()
      Calculates the average of all values for the given integer property over all Objects matching the query.

      For floating-point properties use avg().

      Returns:
      0 in case no elements matched the query

    • count

      public long count()
      The count of non-null values.

      See also: distinct()