RowId (Java SE 15 & JDK 15) (original) (raw)
public interface RowId
The representation (mapping) in the Java programming language of an SQL ROWID value. An SQL ROWID is a built-in type, a value of which can be thought of as an address for its identified row in a database table. Whether that address is logical or, in any respects, physical is determined by its originating data source.
Methods in the interfaces ResultSet
, CallableStatement
, and PreparedStatement
, such as getRowId
and setRowId
allow a programmer to access a SQL ROWID
value. The RowId
interface provides a method for representing the value of the ROWID
as a byte array or as aString
.
The method getRowIdLifetime
in the interface DatabaseMetaData
, can be used to determine if a RowId
object remains valid for the duration of the transaction in which the RowId
was created, the duration of the session in which the RowId
was created, or, effectively, for as long as its identified row is not deleted. In addition to specifying the duration of its valid lifetime outside its originating data source, getRowIdLifetime
specifies the duration of a ROWID
value's valid lifetime within its originating data source. In this, it differs from a large object, because there is no limit on the valid lifetime of a large object within its originating data source.
All methods on the RowId
interface must be fully implemented if the JDBC driver supports the data type.
Since:
1.6
See Also:
Method Summary
Modifier and Type | Method | Description |
---|---|---|
boolean | equals(Object obj) | Compares this RowId to the specified object. |
byte[] | getBytes() | Returns an array of bytes representing the value of the SQL ROWID designated by this java.sql.RowId object. |
int | hashCode() | Returns a hash code value of this RowId object. |
String | toString() | Returns a String representing the value of the SQL ROWID designated by thisjava.sql.RowId object. |
Method Details
equals
boolean equals(Object obj)
Compares thisRowId
to the specified object. The result istrue
if and only if the argument is not null and is a RowId object that represents the same ROWID as this object.
It is important to consider both the origin and the valid lifetime of aRowId
when comparing it to anotherRowId
. If both are valid, and both are from the same table on the same data source, then if they are equal they identify the same row; if one or more is no longer guaranteed to be valid, or if they originate from different data sources, or different tables on the same data source, they may be equal but still not identify the same row.
Overrides:
[equals](../../../java.base/java/lang/Object.html#equals%28java.lang.Object%29)
in class[Object](../../../java.base/java/lang/Object.html "class in java.lang")
Parameters:
obj
- theObject
to compare thisRowId
object against.
Returns:
true if theRowId
s are equal; false otherwise
Since:
1.6
See Also:
Object.hashCode(), HashMapgetBytes
byte[] getBytes()
Returns an array of bytes representing the value of the SQLROWID
designated by thisjava.sql.RowId
object.
Returns:
an array of bytes, whose length is determined by the driver supplying the connection, representing the value of the ROWID designated by this java.sql.RowId object.toString
Returns a String representing the value of the SQL ROWID designated by this
java.sql.RowId
object.
Likejava.sql.Date.toString()
returns the contents of its DATE as theString
"2004-03-17" rather than as DATE literal in SQL (which would have been theString
DATE "2004-03-17"), toString() returns the contents of its ROWID in a form specific to the driver supplying the connection, and possibly not as aROWID
literal.
Overrides:
[toString](../../../java.base/java/lang/Object.html#toString%28%29)
in class[Object](../../../java.base/java/lang/Object.html "class in java.lang")
Returns:
a String whose format is determined by the driver supplying the connection, representing the value of theROWID
designated by thisjava.sql.RowId
object.hashCode
int hashCode()
Returns a hash code value of thisRowId
object.
Overrides:
[hashCode](../../../java.base/java/lang/Object.html#hashCode%28%29)
in class[Object](../../../java.base/java/lang/Object.html "class in java.lang")
Returns:
a hash code for theRowId
See Also:
Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)