org.postgresql.jdbc

Class PgResultSetMetaData

java.lang.Object

org.postgresql.jdbc.PgResultSetMetaData

All Implemented Interfaces:

ResultSetMetaData, Wrapper, PGResultSetMetaData

public class PgResultSetMetaData
extends Object
implements ResultSetMetaData, PGResultSetMetaData

Field Summary

Fields

Modifier and Type	Field and Description
protected BaseConnection	connection
protected Field[]	fields

Fields inherited from interface java.sql.ResultSetMetaData

columnNoNulls, columnNullable, columnNullableUnknown

Constructor Summary

Constructors

Constructor and Description
PgResultSetMetaData(BaseConnection connection, Field[] fields)

Method Summary

Methods

Modifier and Type	Method and Description
String	getBaseColumnName(int column) Returns the underlying column name of a query result, or "" if it is unable to be determined.
String	getBaseSchemaName(int column) Returns the underlying schema name of query result, or "" if it is unable to be determined.
String	getBaseTableName(int column) Returns the underlying table name of query result, or "" if it is unable to be determined.
String	getCatalogName(int column) Gets the designated column's table's catalog name.
String	getColumnClassName(int column) Returns the fully-qualified name of the Java class whose instances are manufactured if the method ResultSet.getObject is called to retrieve a value from the column.
int	getColumnCount() Returns the number of columns in this ResultSet object.
int	getColumnDisplaySize(int column) Indicates the designated column's normal maximum width in characters.
String	getColumnLabel(int column) Gets the designated column's suggested title for use in printouts and displays.
String	getColumnName(int column) Get the designated column's name.
int	getColumnType(int column) Retrieves the designated column's SQL type.
String	getColumnTypeName(int column) Retrieves the designated column's database-specific type name.
protected Field	getField(int columnIndex)
int	getFormat(int column) Is a column Text or Binary?
protected String	getPGType(int columnIndex)
int	getPrecision(int column) Get the designated column's specified column size.
int	getScale(int column) Gets the designated column's number of digits to right of the decimal point. 0 is returned for data types where the scale is not applicable.
String	getSchemaName(int column) Get the designated column's table's schema.
protected int	getSQLType(int columnIndex)
String	getTableName(int column) Gets the designated column's table name.
boolean	isAutoIncrement(int column) Indicates whether the designated column is automatically numbered.
boolean	isCaseSensitive(int column) Indicates whether a column's case matters.
boolean	isCurrency(int column) Indicates whether the designated column is a cash value.
boolean	isDefinitelyWritable(int column) Indicates whether a write on the designated column will definitely succeed.
int	isNullable(int column) Indicates the nullability of values in the designated column.
boolean	isReadOnly(int column) Indicates whether the designated column is definitely not writable.
boolean	isSearchable(int column) Indicates whether the designated column can be used in a where clause.
boolean	isSigned(int column) Indicates whether values in the designated column are signed numbers.
boolean	isWrapperFor(Class<?> iface) Returns true if this either implements the interface argument or is directly or indirectly a wrapper for an object that does.
boolean	isWritable(int column) Indicates whether it is possible for a write on the designated column to succeed.
<T> T	unwrap(Class<T> iface) Returns an object that implements the given interface to allow access to non-standard methods, or standard methods not exposed by the proxy.

Methods inherited from class java.lang.Object

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

Field Detail

connection

protected final BaseConnection connection

fields

protected final Field[] fields

Constructor Detail

PgResultSetMetaData

public PgResultSetMetaData(BaseConnection connection,
                   Field[] fields)

Method Detail

getColumnCount

public int getColumnCount()
                   throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Returns the number of columns in this ResultSet object.

Specified by:

getColumnCount in interface ResultSetMetaData

Returns:

the number of columns

Throws:

SQLException - if a database access error occurs

isAutoIncrement

public boolean isAutoIncrement(int column)
                        throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Indicates whether the designated column is automatically numbered.

Specified by:

isAutoIncrement in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so; false otherwise

Throws:

SQLException - if a database access error occurs

isCaseSensitive

public boolean isCaseSensitive(int column)
                        throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Indicates whether a column's case matters.

Specified by:

isCaseSensitive in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so; false otherwise

Throws:

SQLException - if a database access error occurs

isSearchable

public boolean isSearchable(int column)
                     throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Indicates whether the designated column can be used in a where clause.

Specified by:

isSearchable in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so; false otherwise

Throws:

SQLException - if a database access error occurs

isCurrency

public boolean isCurrency(int column)
                   throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Indicates whether the designated column is a cash value.

Specified by:

isCurrency in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so; false otherwise

Throws:

SQLException - if a database access error occurs

isNullable

public int isNullable(int column)
               throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Indicates the nullability of values in the designated column.

Specified by:

isNullable in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

the nullability status of the given column; one of columnNoNulls, columnNullable or columnNullableUnknown

Throws:

SQLException - if a database access error occurs

isSigned

public boolean isSigned(int column)
                 throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Indicates whether values in the designated column are signed numbers.

Specified by:

isSigned in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so; false otherwise

Throws:

SQLException - if a database access error occurs

getColumnDisplaySize

public int getColumnDisplaySize(int column)
                         throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Indicates the designated column's normal maximum width in characters.

Specified by:

getColumnDisplaySize in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

the normal maximum number of characters allowed as the width of the designated column

Throws:

SQLException - if a database access error occurs

getColumnLabel

public String getColumnLabel(int column)
                      throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Gets the designated column's suggested title for use in printouts and displays. The suggested title is usually specified by the SQL AS clause. If a SQL AS is not specified, the value returned from getColumnLabel will be the same as the value returned by the getColumnName method.

Specified by:

getColumnLabel in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

the suggested column title

Throws:

SQLException - if a database access error occurs

getColumnName

public String getColumnName(int column)
                     throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Get the designated column's name.

Specified by:

getColumnName in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

column name

Throws:

SQLException - if a database access error occurs

getBaseColumnName

public String getBaseColumnName(int column)
                         throws SQLException

Description copied from interface: PGResultSetMetaData

Returns the underlying column name of a query result, or "" if it is unable to be determined.

Specified by:

getBaseColumnName in interface PGResultSetMetaData

Parameters:

column - column position (1-based)

Returns:

underlying column name of a query result

Throws:

SQLException - if something wrong happens

getSchemaName

public String getSchemaName(int column)
                     throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Get the designated column's table's schema.

Specified by:

getSchemaName in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

schema name or "" if not applicable

Throws:

SQLException - if a database access error occurs

getBaseSchemaName

public String getBaseSchemaName(int column)
                         throws SQLException

Description copied from interface: PGResultSetMetaData

Returns the underlying schema name of query result, or "" if it is unable to be determined.

Specified by:

getBaseSchemaName in interface PGResultSetMetaData

Parameters:

column - column position (1-based)

Returns:

underlying schema name of query result

Throws:

SQLException - if something wrong happens

getPrecision

public int getPrecision(int column)
                 throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Get the designated column's specified column size. For numeric data, this is the maximum precision. For character data, this is the length in characters. For datetime datatypes, this is the length in characters of the String representation (assuming the maximum allowed precision of the fractional seconds component). For binary data, this is the length in bytes. For the ROWID datatype, this is the length in bytes. 0 is returned for data types where the column size is not applicable.

Specified by:

getPrecision in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

precision

Throws:

SQLException - if a database access error occurs

getScale

public int getScale(int column)
             throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Gets the designated column's number of digits to right of the decimal point. 0 is returned for data types where the scale is not applicable.

Specified by:

getScale in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

scale

Throws:

SQLException - if a database access error occurs

getTableName

public String getTableName(int column)
                    throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Gets the designated column's table name.

Specified by:

getTableName in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

table name or "" if not applicable

Throws:

SQLException - if a database access error occurs

getBaseTableName

public String getBaseTableName(int column)
                        throws SQLException

Description copied from interface: PGResultSetMetaData

Returns the underlying table name of query result, or "" if it is unable to be determined.

Specified by:

getBaseTableName in interface PGResultSetMetaData

Parameters:

column - column position (1-based)

Returns:

underlying table name of query result

Throws:

SQLException - if something wrong happens

getCatalogName

public String getCatalogName(int column)
                      throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Gets the designated column's table's catalog name.

Specified by:

getCatalogName in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

the name of the catalog for the table in which the given column appears or "" if not applicable

Throws:

SQLException - if a database access error occurs

getColumnType

public int getColumnType(int column)
                  throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Retrieves the designated column's SQL type.

Specified by:

getColumnType in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

SQL type from java.sql.Types

Throws:

SQLException - if a database access error occurs

See Also:

Types

getFormat

public int getFormat(int column)
              throws SQLException

Description copied from interface: PGResultSetMetaData

Is a column Text or Binary?

Specified by:

getFormat in interface PGResultSetMetaData

Parameters:

column - column position (1-based)

Returns:

if column is Text or Binary

Throws:

SQLException - if something wrong happens

See Also:

Field.BINARY_FORMAT, Field.TEXT_FORMAT

getColumnTypeName

public String getColumnTypeName(int column)
                         throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Retrieves the designated column's database-specific type name.

Specified by:

getColumnTypeName in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

type name used by the database. If the column type is a user-defined type, then a fully-qualified type name is returned.

Throws:

SQLException - if a database access error occurs

isReadOnly

public boolean isReadOnly(int column)
                   throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Indicates whether the designated column is definitely not writable.

Specified by:

isReadOnly in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so; false otherwise

Throws:

SQLException - if a database access error occurs

isWritable

public boolean isWritable(int column)
                   throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Indicates whether it is possible for a write on the designated column to succeed.

Specified by:

isWritable in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so; false otherwise

Throws:

SQLException - if a database access error occurs

isDefinitelyWritable

public boolean isDefinitelyWritable(int column)
                             throws SQLException

Description copied from interface: java.sql.ResultSetMetaData

Indicates whether a write on the designated column will definitely succeed.

Specified by:

isDefinitelyWritable in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so; false otherwise

Throws:

SQLException - if a database access error occurs

getField

protected Field getField(int columnIndex)
                  throws SQLException

Throws:

SQLException

getPGType

protected String getPGType(int columnIndex)
                    throws SQLException

Throws:

SQLException

getSQLType

protected int getSQLType(int columnIndex)
                  throws SQLException

Throws:

SQLException

getColumnClassName

public String getColumnClassName(int column)
                          throws SQLException

Returns the fully-qualified name of the Java class whose instances are manufactured if the method ResultSet.getObject is called to retrieve a value from the column. ResultSet.getObject may return a subclass of the class returned by this method.

Specified by:

getColumnClassName in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

the fully-qualified name of the class in the Java programming language that would be used by the method ResultSet.getObject to retrieve the value in the specified column. This is the class name used for custom mapping.

Throws:

SQLException - if a database access error occurs

isWrapperFor

public boolean isWrapperFor(Class<?> iface)
                     throws SQLException

Description copied from interface: java.sql.Wrapper

Returns true if this either implements the interface argument or is directly or indirectly a wrapper for an object that does. Returns false otherwise. If this implements the interface then return true, else if this is a wrapper then return the result of recursively calling isWrapperFor on the wrapped object. If this does not implement the interface and is not a wrapper, return false. This method should be implemented as a low-cost operation compared to unwrap so that callers can use this method to avoid expensive unwrap calls that may fail. If this method returns true then calling unwrap with the same argument should succeed.

Specified by:

isWrapperFor in interface Wrapper

Parameters:

iface - a Class defining an interface.

Returns:

true if this implements the interface or directly or indirectly wraps an object that does.

Throws:

SQLException - if an error occurs while determining whether this is a wrapper for an object with the given interface.

unwrap

public <T> T unwrap(Class<T> iface)
         throws SQLException

Description copied from interface: java.sql.Wrapper

Returns an object that implements the given interface to allow access to non-standard methods, or standard methods not exposed by the proxy. If the receiver implements the interface then the result is the receiver or a proxy for the receiver. If the receiver is a wrapper and the wrapped object implements the interface then the result is the wrapped object or a proxy for the wrapped object. Otherwise return the the result of calling unwrap recursively on the wrapped object or a proxy for that result. If the receiver is not a wrapper and does not implement the interface, then an SQLException is thrown.

Specified by:

unwrap in interface Wrapper

Parameters:

iface - A Class defining an interface that the result must implement.

Returns:

an object that implements the interface. May be a proxy for the actual implementing object.

Throws:

SQLException - If no object found that implements the interface