Skip navigation links
com.supermap.data

Class JoinItem


  • public class JoinItem
extends InternalHandleDisposable

    The connection information class.

    The JoinItem class is used to define the join information between the vector dataset and the exterior table. The exterior table can be the DBMS table of another vector dataset (including the tabular dataset, which has no geometry field) or the table in a database defined by the user. Note that the vector dataset and the exterior table should exist in the same datasource.

    Once the two tables are joined together, you can perform query, mapping and analysis etc. on the exterior table via the main table, here, the vector dataset. When the relationship between two tables is one-to-one or many-to-one, you can use join to connect them, and especially, under many-to-one relationship, it is allowed to specify multiple associations, that is, there can be multiple associated field pairs. The instance of this class can be created.

    • Constructor Summary

      Constructors 
      Constructor and Description
      JoinItem()
      Constructs a new JoinItem object.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method and Description
      void dispose()
      Releases the resources that the object occupies.
      java.lang.String getForeignTable()
      Returns the name of the external table.
      java.lang.String getJoinFilter()
      Returns the joint expression between the vector dataset and the foreign table, i.e., sets the related fields between the two tables.
      JoinType getJoinType()
      Returns the join type of the two tables.
      java.lang.String getName()
      Returns the name of the JoinItem object.
      void setForeignTable(java.lang.String value)
      Sets the name of the external table.
      void setJoinFilter(java.lang.String value)
      Sets the joint expression between the vector dataset and the foreign table, i.e., sets the related fields between the two tables.
      void setJoinType(JoinType value)
      Sets the join type of the two tables.
      void setName(java.lang.String value)
      Sets the name of this JoinItem object.
      java.lang.String toString()
      Outputs this JoinItem object to a readable string, the format is {Name="",ForeignTable="",JoinFilter="",JoinType=}.

      • Methods inherited from class java.lang.Object

        equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

    • Constructor Detail

      • JoinItem

        public JoinItem()
        Constructs a new JoinItem object.

    • Method Detail

      • getForeignTable

        public java.lang.String getForeignTable()
        Returns the name of the external table.
        Returns:
        The name of the external table.
        Default:
        The default value is an empty string.

      • setForeignTable

        public void setForeignTable(java.lang.String value)
        Sets the name of the external table.
        Parameters:
        value - The name of the external table.
        Example:
        Please refer to the example for the JoinItem class.

      • getJoinFilter

        public java.lang.String getJoinFilter()
        Returns the joint expression between the vector dataset and the foreign table, i.e., sets the related fields between the two tables. For example, let us connect the 'district' field of a region dataset (Building) about housing and the "region" field of an attribute datasets (Owner) about house owners . Names of the two datasets are Table_Building and Table_Owner respectively. The connection expression is Table_Building.district = Table_Owner.region. When multiple fields are connected, please use AND to connect them.
        Returns:
        The related fields between the two tables.
        Default:
        The default value is an empty string.

      • setJoinFilter

        public void setJoinFilter(java.lang.String value)
        Sets the joint expression between the vector dataset and the foreign table, i.e., sets the related fields between the two tables. For example, let us connect the "district" field of a region dataset (Building) about housing and the "region" field of an attribute datasets (Owner) about house owners . Names of the two datasets are Table_Building and Table_Owner respectively. The connection expression is Table_Building.district = Table_Owner.region. When multiple fields are connected, please use AND to connect them.
        Parameters:
        value - The related fields between the two tables.
        Example:
        Please refer to the example for the JoinItem class.

      • getJoinType

        public JoinType getJoinType()
        Returns the join type of the two tables. Join type is used when performing query on the two joined tables, and will determine which records among the records that meet the query condition will be returned.
        Returns:
        The join type between two tables.
        Default:
        The default value is LEFTJOIN

      • setJoinType

        public void setJoinType(JoinType value)
        Sets the join type of the two tables. Join type is used when performing query on the two joined tables, and will determine which records among the records that meet the query condition will be returned.
        Parameters:
        value - The join type between two tables.
        Example:
        Please refer to the example for the JoinItem class.

      • getName

        public java.lang.String getName()
        Returns the name of the JoinItem object.
        Returns:
        The name of the JoinItem object.
        Default:
        The default value is "UntitledJoinItem".

      • setName

        public void setName(java.lang.String value)
        Sets the name of this JoinItem object.
        Parameters:
        value - The name of the JoinItem object.
        Example:
        Please refer to the example for the JoinItem class.

      • dispose

        public void dispose()
        Releases the resources that the object occupies. This object is no longer available when the method is called.

      • toString

        public java.lang.String toString()
        Outputs this JoinItem object to a readable string, the format is {Name="",ForeignTable="",JoinFilter="",JoinType=}.
        Overrides:
        toString in class java.lang.Object
        Returns:
        A string that of the JoinItem object.
Skip navigation links