Class HashBasedTable<R,​C,​V>

  • All Implemented Interfaces:
    Table<R,​C,​V>, java.io.Serializable

    public class HashBasedTable<R,​C,​V>
    extends StandardTable<R,​C,​V>
    Implementation of Table using linked hash tables. This guarantees predictable iteration order of the various views.

    The views returned by StandardTable.column(C), StandardTable.columnKeySet(), and StandardTable.columnMap() have iterators that don't support remove(). Otherwise, all optional operations are supported. Null row keys, columns keys, and values are not supported.

    Lookups by row key are often faster than lookups by column key, because the data is stored in a Map<R, Map<C, V>>. A method call like column(columnKey).get(rowKey) still runs quickly, since the row key is provided. However, column(columnKey).size() takes longer, since an iteration across all row keys occurs.

    Note that this implementation is not synchronized. If multiple threads access this table concurrently and one of the threads modifies the table, it must be synchronized externally.

    See the Guava User Guide article on Table.

    Since:
    7.0
    See Also:
    Serialized Form
    • Constructor Detail

    • Method Detail

      • create

        public static <R,​C,​V> HashBasedTable<R,​C,​V> create()
        Creates an empty HashBasedTable.
      • create

        public static <R,​C,​V> HashBasedTable<R,​C,​V> create​(int expectedRows,
                                                                                   int expectedCellsPerRow)
        Creates an empty HashBasedTable with the specified map sizes.
        Parameters:
        expectedRows - the expected number of distinct row keys
        expectedCellsPerRow - the expected number of column key / value mappings in each row
        Throws:
        java.lang.IllegalArgumentException - if expectedRows or expectedCellsPerRow is negative
      • create

        public static <R,​C,​V> HashBasedTable<R,​C,​V> create​(Table<? extends R,​? extends C,​? extends V> table)
        Creates a HashBasedTable with the same mappings as the specified table.
        Parameters:
        table - the table to copy
        Throws:
        java.lang.NullPointerException - if any of the row keys, column keys, or values in table is null