nz.co.gregs.dbvolution.datatypes.spatial2D

Class DBPolygon2D

java.lang.Object

nz.co.gregs.dbvolution.datatypes.QueryableDatatype<com.vividsolutions.jts.geom.Polygon>

nz.co.gregs.dbvolution.datatypes.spatial2D.DBPolygon2D

All Implemented Interfaces:

Serializable, TransformRequiredForSelectClause, DBExpression, SpatialResult, ExpressionCanHaveNullValues, ExpressionHasStandardStringResult, Polygon2DResult, Spatial2DResult

public class DBPolygon2D
extends QueryableDatatype<com.vividsolutions.jts.geom.Polygon>
implements TransformRequiredForSelectClause, Polygon2DResult

Represents database columns and values that are a 2 dimensional polygon: an closed ordered set of X and Y values defining a solid shape.

Use DBPolygon2D when the column is a 2 dimensional Polygon, ST_Polygon, or GEOMETRY that represents a polygon.

Generally DBPolygon2D is declared inside your DBRow sub-class as: @DBColumn public DBPolygon2D myPolygonColumn = new DBPolygon2D();

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Author:

Gregory Graham

See Also:

Serialized Form

Field Summary

Fields inherited from class nz.co.gregs.dbvolution.datatypes.QueryableDatatype

SORT_ASCENDING, SORT_DESCENDING

Constructor Summary

Constructors

Constructor and Description
DBPolygon2D() Create an unset undefined DBPolygon2D object to represent a Polygon column or value.
DBPolygon2D(com.vividsolutions.jts.geom.Polygon polygon) Create DBPolygon2D and set it's value to the JTS Polygon provided.
DBPolygon2D(Polygon2DExpression columnExpression) Create a DBPolygon2D with the column expression specified.

Method Summary

Methods

Modifier and Type	Method and Description
protected String	formatValueForSQLStatement(DBDefinition db) Returns the value of the object formatted for the database This should be overridden in each subclass This method is called by toSQLString after checking for NULLs and should return a string representation of the object formatted for use within a SQL select, insert, update, or delete statement.
protected com.vividsolutions.jts.geom.Polygon	getFromResultSet(DBDefinition database, ResultSet resultSet, String fullColumnName) Returns the correct object from the ResultSet for the QueryableDatatype to handle.
boolean	getIncludesNull() Returns TRUE if this expression requires support for possible NULL database values.
String	getSQLDatatype() Provides the SQL datatype used by default for this type of object.
com.vividsolutions.jts.geom.Polygon	getValue() Gets the current literal value of this queryable data type.
boolean	isAggregator() Returns TRUE if this expression is an Aggregator like SUM() or LEAST().
com.vividsolutions.jts.geom.Polygon	jtsPolygonValue() Convert the value of this object to a JTS Polygon.
void	setValue(com.vividsolutions.jts.geom.Polygon polygon) Set the value of this DBPolygon2D to the Polygon specified.
protected void	setValueFromStandardStringEncoding(String encodedValue) Set the value of this QDT to the value provided from the standard string encoding of this datatype
StringExpression	stringResult() Converts the expression into the standard string/character expression representing the value.

Methods inherited from class nz.co.gregs.dbvolution.datatypes.QueryableDatatype

clear, copy, equals, formatColumnForSQLStatement, getColumnExpression, getLiteralValue, getOperator, getPreviousSQLValue, getPreviousValue, getPropertyWrapperDefinition, getQueryableDatatypeForExpressionValue, getQueryableDatatypeForObject, getQueryableDatatypeInstance, getSortOrder, getTablesInvolved, hasBeenSet, hasChanged, hasColumnExpression, hashCode, includingNulls, isDefined, isNotNull, isNull, isPurelyFunctional, negateOperator, removeConstraints, setChanged, setColumnExpression, setDefined, setFromResultSet, setLiteralValue, setOperator, setPreviousValue, setSortOrderAscending, setSortOrderDescending, setToNull, setToNull, setUnchanged, setValueToNull, stringValue, toSQLString, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface nz.co.gregs.dbvolution.expressions.DBExpression

copy, getQueryableDatatypeForExpressionValue, getTablesInvolved, isPurelyFunctional, toSQLString

Constructor Detail

DBPolygon2D

public DBPolygon2D()

Create an unset undefined DBPolygon2D object to represent a Polygon column or value.

DBPolygon2D

public DBPolygon2D(Polygon2DExpression columnExpression)

Create a DBPolygon2D with the column expression specified.

When retrieving this object from the database the expression will be evaluated to provide the value.

Parameters:

columnExpression -

DBPolygon2D

public DBPolygon2D(com.vividsolutions.jts.geom.Polygon polygon)

Create DBPolygon2D and set it's value to the JTS Polygon provided.

Equivalent to {code polygon2D = new DBPolygon2D(); polygon2D.setValue(aPolygon);}

Parameters:

polygon -

Method Detail

setValue

public void setValue(com.vividsolutions.jts.geom.Polygon polygon)

Set the value of this DBPolygon2D to the Polygon specified.

Set values are used to add the value to the database. Without a set value the database entry will be NULL.

Parameters:

polygon - the value to be set in the database.

getSQLDatatype

public String getSQLDatatype()

Description copied from class: QueryableDatatype

Provides the SQL datatype used by default for this type of object.

This should be overridden in each subclass

Example return value: "VARCHAR(1000)"

Database specific datatypes are provided by the DBDefinition in the method DBDefinition.getDatabaseDataTypeOfQueryableDatatype(nz.co.gregs.dbvolution.datatypes.QueryableDatatype<?>)

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Specified by:

getSQLDatatype in class QueryableDatatype<com.vividsolutions.jts.geom.Polygon>

Returns:

the standard SQL datatype that corresponds to this QDT as a String

formatValueForSQLStatement

protected String formatValueForSQLStatement(DBDefinition db)

Description copied from class: QueryableDatatype

Returns the value of the object formatted for the database This should be overridden in each subclass This method is called by toSQLString after checking for NULLs and should return a string representation of the object formatted for use within a SQL select, insert, update, or delete statement. For Example: DBString{yada} => 'yada' DBInteger{1234} => 123 DBDate{1/March/2013} => TO_DATE('20130301', 'YYYYMMDD')

Specified by:

formatValueForSQLStatement in class QueryableDatatype<com.vividsolutions.jts.geom.Polygon>

Parameters:

db - db

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Returns:

the literal value translated to a String ready to insert into an SQL statement

getFromResultSet

protected com.vividsolutions.jts.geom.Polygon getFromResultSet(DBDefinition database,
                                                   ResultSet resultSet,
                                                   String fullColumnName)
                                                        throws SQLException

Description copied from class: QueryableDatatype

Returns the correct object from the ResultSet for the QueryableDatatype to handle.

Specified by:

getFromResultSet in class QueryableDatatype<com.vividsolutions.jts.geom.Polygon>

Parameters:

database - database

resultSet - resultSet

fullColumnName - fullColumnName

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Returns:

the expected object from the ResultSet. 1 Database exceptions may be thrown

Throws:

SQLException - java.sql.SQLException

jtsPolygonValue

public com.vividsolutions.jts.geom.Polygon jtsPolygonValue()

Convert the value of this object to a JTS Polygon.

NULL is valid result from this method.

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Returns:

the set value of this object as a JTS Polygon object.

getValue

public com.vividsolutions.jts.geom.Polygon getValue()

Description copied from class: QueryableDatatype

Gets the current literal value of this queryable data type. The returned value should be in the correct type as appropriate for the type of queryable data type.

This method will return NULL if the QDT represents a database NULL OR the field is undefined. Use QueryableDatatype.isNull() and QueryableDatatype.isDefined() to differentiate the 2 states.

Undefined QDTs represents a QDT that is not a field from the database. Undefined QDTs are similar to undefined DBRows

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Overrides:

getValue in class QueryableDatatype<com.vividsolutions.jts.geom.Polygon>

Returns:

the literal value, if defined, which may be null

isAggregator

public boolean isAggregator()

Description copied from interface: DBExpression

Returns TRUE if this expression is an Aggregator like SUM() or LEAST().

Subclasses must implement this method returning TRUE if the expression will combine the results of several rows to produce a result. If the expression relies on subexpressions, then the isAggregator method must return TRUE if the subexpressions include an aggregator.

Aggregators collect several rows together to produce a single result. Examples are MAX, MIN, and AVERAGE.

They are only appropriate in the SELECT clause and generally require the GROUP BY clause to be useful.

Aggregators are used with DBReport. Aggregator expressions are included in the SELECT clause but excluded from the GROUP BY clause.

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Specified by:

isAggregator in interface DBExpression

Returns:

TRUE if this DBExpression represents an aggregating functions

getIncludesNull

public boolean getIncludesNull()

Description copied from interface: ExpressionCanHaveNullValues

Returns TRUE if this expression requires support for possible NULL database values.

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Specified by:

getIncludesNull in interface ExpressionCanHaveNullValues

Returns:

TRUE if the expression should check for NULLs, FALSE otherwise.

stringResult

public StringExpression stringResult()

Description copied from interface: ExpressionHasStandardStringResult

Converts the expression into the standard string/character expression representing the value.

Not all types have a standard string/character representation, notably dates.

Please note that this is not the SQL version of the expression (toSQLString() will provide that), nor does this provide a String of the value.

To get the string value use the stringValue method of the appropriate QDT.

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Specified by:

stringResult in interface ExpressionHasStandardStringResult

Returns:

a StringExpression of the expression.

setValueFromStandardStringEncoding

protected void setValueFromStandardStringEncoding(String encodedValue)

Description copied from class: QueryableDatatype

Set the value of this QDT to the value provided from the standard string encoding of this datatype

Subclass writers should ensure that the method handles nulls correctly and throws an exception if an inappropriate value is supplied.

Specified by:

setValueFromStandardStringEncoding in class QueryableDatatype<com.vividsolutions.jts.geom.Polygon>

Parameters:

encodedValue - the value of the QDT in the appropriate encoding