Array

  • The Array interface in Java represents SQL ARRAY types, acting as a pointer to the data and providing methods for retrieval, custom mapping, and resource management.

  • Array supports retrieving the entire array or a slice as a Java array or a ResultSet using methods like getArray() and getResultSet().

  • Custom mapping of UDT elements within an array is achieved by implementing the SQLData interface and using type maps.

  • The getResultSet() method provides flexible ways to retrieve array elements as a ResultSet, offering variations for selecting subarrays and applying custom type mapping.

  • Type maps, either provided to the method or associated with the connection, play a key role in controlling the mapping of array elements to Java types.
public interface Array

The mapping in the Java programming language for the SQL type ARRAY. By default, an Array value is a transaction-duration reference to an SQL ARRAY value. By default, an Array object is implemented using an SQL LOCATOR(array) internally, which means that an Array object contains a logical pointer to the data in the SQL ARRAY value rather than containing the ARRAY value's data.

The Array interface provides methods for bringing an SQL ARRAY value's data to the client as either an array or a ResultSet object. If the elements of the SQL ARRAY are a UDT, they may be custom mapped. To create a custom mapping, a programmer must do two things:

  • create a class that implements the SQLData interface for the UDT to be custom mapped.
  • make an entry in a type map that contains
    • the fully-qualified SQL type name of the UDT
    • the Class object for the class implementing SQLData

When a type map with an entry for the base type is supplied to the methods getArray and getResultSet, the mapping it contains will be used to map the elements of the ARRAY value. If no type map is supplied, which would typically be the case, the connection's type map is used by default. If the connection's type map or a type map supplied to a method has no entry for the base type, the elements are mapped according to the standard mapping.

All methods on the Array interface must be fully implemented if the JDBC driver supports the data type.

Public Method Summary

abstract void
free()
This method frees the Array object and releases the resources that it holds.
abstract Object
getArray(Map<String, Class<?>> map)
Retrieves the contents of the SQL ARRAY value designated by this Array object.
abstract Object
getArray()
Retrieves the contents of the SQL ARRAY value designated by this Array object in the form of an array in the Java programming language.
abstract Object
getArray(long index, int count, Map<String, Class<?>> map)
Retreives a slice of the SQL ARRAY value designated by this Array object, beginning with the specified index and containing up to count successive elements of the SQL array.
abstract Object
getArray(long index, int count)
Retrieves a slice of the SQL ARRAY value designated by this Array object, beginning with the specified index and containing up to count successive elements of the SQL array.
abstract int
getBaseType()
Retrieves the JDBC type of the elements in the array designated by this Array object.
abstract String
getBaseTypeName()
Retrieves the SQL type name of the elements in the array designated by this Array object.
abstract ResultSet
getResultSet()
Retrieves a result set that contains the elements of the SQL ARRAY value designated by this Array object.
abstract ResultSet
getResultSet(Map<String, Class<?>> map)
Retrieves a result set that contains the elements of the SQL ARRAY value designated by this Array object.
abstract ResultSet
getResultSet(long index, int count, Map<String, Class<?>> map)
Retrieves a result set holding the elements of the subarray that starts at index index and contains up to count successive elements.
abstract ResultSet
getResultSet(long index, int count)
Retrieves a result set holding the elements of the subarray that starts at index index and contains up to count successive elements.

Public Methods

public abstract void free ()

This method frees the Array object and releases the resources that it holds. The object is invalid once the free method is called.

After free has been called, any attempt to invoke a method other than free will result in a SQLException being thrown. If free is called multiple times, the subsequent calls to free are treated as a no-op.

Throws
SQLException if an error occurs releasing the Array's resources
SQLFeatureNotSupportedException if the JDBC driver does not support this method

public abstract Object getArray (Map<String, Class<?>> map)

Retrieves the contents of the SQL ARRAY value designated by this Array object. This method uses the specified map for type map customizations unless the base type of the array does not match a user-defined type in map, in which case it uses the standard mapping. This version of the method getArray uses either the given type map or the standard mapping; it never uses the type map associated with the connection.

Note: When getArray is used to materialize a base type that maps to a primitive data type, then it is implementation-defined whether the array returned is an array of that primitive data type or an array of Object.

Parameters
map a java.util.Map object that contains mappings of SQL type names to classes in the Java programming language
Returns
  • an array in the Java programming language that contains the ordered elements of the SQL array designated by this object
Throws
SQLException if an error occurs while attempting to access the array
SQLFeatureNotSupportedException if the JDBC driver does not support this method

public abstract Object getArray ()

Retrieves the contents of the SQL ARRAY value designated by this Array object in the form of an array in the Java programming language. This version of the method getArray uses the type map associated with the connection for customizations of the type mappings.

Note: When getArray is used to materialize a base type that maps to a primitive data type, then it is implementation-defined whether the array returned is an array of that primitive data type or an array of Object.

Returns
  • an array in the Java programming language that contains the ordered elements of the SQL ARRAY value designated by this Array object
Throws
SQLException if an error occurs while attempting to access the array
SQLFeatureNotSupportedException if the JDBC driver does not support this method

public abstract Object getArray (long index, int count, Map<String, Class<?>> map)

Retreives a slice of the SQL ARRAY value designated by this Array object, beginning with the specified index and containing up to count successive elements of the SQL array.

This method uses the specified map for type map customizations unless the base type of the array does not match a user-defined type in map, in which case it uses the standard mapping. This version of the method getArray uses either the given type map or the standard mapping; it never uses the type map associated with the connection.

Note: When getArray is used to materialize a base type that maps to a primitive data type, then it is implementation-defined whether the array returned is an array of that primitive data type or an array of Object.

Parameters
index the array index of the first element to retrieve; the first element is at index 1
count the number of successive SQL array elements to retrieve
map a java.util.Map object that contains SQL type names and the classes in the Java programming language to which they are mapped
Returns
  • an array containing up to count consecutive elements of the SQL ARRAY value designated by this Array object, beginning with element index
Throws
SQLException if an error occurs while attempting to access the array
SQLFeatureNotSupportedException if the JDBC driver does not support this method

public abstract Object getArray (long index, int count)

Retrieves a slice of the SQL ARRAY value designated by this Array object, beginning with the specified index and containing up to count successive elements of the SQL array. This method uses the type map associated with the connection for customizations of the type mappings.

Note: When getArray is used to materialize a base type that maps to a primitive data type, then it is implementation-defined whether the array returned is an array of that primitive data type or an array of Object.

Parameters
index the array index of the first element to retrieve; the first element is at index 1
count the number of successive SQL array elements to retrieve
Returns
  • an array containing up to count consecutive elements of the SQL array, beginning with element index
Throws
SQLException if an error occurs while attempting to access the array
SQLFeatureNotSupportedException if the JDBC driver does not support this method

public abstract int getBaseType ()

Retrieves the JDBC type of the elements in the array designated by this Array object.

Returns
  • a constant from the class Types that is the type code for the elements in the array designated by this Array object
Throws
SQLException if an error occurs while attempting to access the base type
SQLFeatureNotSupportedException if the JDBC driver does not support this method

public abstract String getBaseTypeName ()

Retrieves the SQL type name of the elements in the array designated by this Array object. If the elements are a built-in type, it returns the database-specific type name of the elements. If the elements are a user-defined type (UDT), this method returns the fully-qualified SQL type name.

Returns
  • a String that is the database-specific name for a built-in base type; or the fully-qualified SQL type name for a base type that is a UDT
Throws
SQLException if an error occurs while attempting to access the type name
SQLFeatureNotSupportedException if the JDBC driver does not support this method

public abstract ResultSet getResultSet ()

Retrieves a result set that contains the elements of the SQL ARRAY value designated by this Array object. If appropriate, the elements of the array are mapped using the connection's type map; otherwise, the standard mapping is used.

The result set contains one row for each array element, with two columns in each row. The second column stores the element value; the first column stores the index into the array for that element (with the first array element being at index 1). The rows are in ascending order corresponding to the order of the indices.

Returns
  • a ResultSet object containing one row for each of the elements in the array designated by this Array object, with the rows in ascending order based on the indices.
Throws
SQLException if an error occurs while attempting to access the array
SQLFeatureNotSupportedException if the JDBC driver does not support this method

public abstract ResultSet getResultSet (Map<String, Class<?>> map)

Retrieves a result set that contains the elements of the SQL ARRAY value designated by this Array object. This method uses the specified map for type map customizations unless the base type of the array does not match a user-defined type in map, in which case it uses the standard mapping. This version of the method getResultSet uses either the given type map or the standard mapping; it never uses the type map associated with the connection.

The result set contains one row for each array element, with two columns in each row. The second column stores the element value; the first column stores the index into the array for that element (with the first array element being at index 1). The rows are in ascending order corresponding to the order of the indices.

Parameters
map contains the mapping of SQL user-defined types to classes in the Java programming language
Returns
  • a ResultSet object containing one row for each of the elements in the array designated by this Array object, with the rows in ascending order based on the indices.
Throws
SQLException if an error occurs while attempting to access the array
SQLFeatureNotSupportedException if the JDBC driver does not support this method

public abstract ResultSet getResultSet (long index, int count, Map<String, Class<?>> map)

Retrieves a result set holding the elements of the subarray that starts at index index and contains up to count successive elements. This method uses the specified map for type map customizations unless the base type of the array does not match a user-defined type in map, in which case it uses the standard mapping. This version of the method getResultSet uses either the given type map or the standard mapping; it never uses the type map associated with the connection.

The result set has one row for each element of the SQL array designated by this object, with the first row containing the element at index index. The result set has up to count rows in ascending order based on the indices. Each row has two columns: The second column stores the element value; the first column stroes the index into the array for that element.

Parameters
index the array index of the first element to retrieve; the first element is at index 1
count the number of successive SQL array elements to retrieve
map the Map object that contains the mapping of SQL type names to classes in the Java(tm) programming language
Returns
  • a ResultSet object containing up to count consecutive elements of the SQL array designated by this Array object, starting at index index.
Throws
SQLException if an error occurs while attempting to access the array
SQLFeatureNotSupportedException if the JDBC driver does not support this method

public abstract ResultSet getResultSet (long index, int count)

Retrieves a result set holding the elements of the subarray that starts at index index and contains up to count successive elements. This method uses the connection's type map to map the elements of the array if the map contains an entry for the base type. Otherwise, the standard mapping is used.

The result set has one row for each element of the SQL array designated by this object, with the first row containing the element at index index. The result set has up to count rows in ascending order based on the indices. Each row has two columns: The second column stores the element value; the first column stores the index into the array for that element.

Parameters
index the array index of the first element to retrieve; the first element is at index 1
count the number of successive SQL array elements to retrieve
Returns
  • a ResultSet object containing up to count consecutive elements of the SQL array designated by this Array object, starting at index index.
Throws
SQLException if an error occurs while attempting to access the array
SQLFeatureNotSupportedException if the JDBC driver does not support this method