MultiPolygon

Constructs a <code>MultiPolygon</code>.

Computes the boundary of this geometry

return a lineal geometry (which may be empty)

Creates a {link MultiPolygon} with every component reversed. The order of the components in the collection are not reversed.

return a MultiPolygon in the reverse order

Computes a buffer area around this geometry having the given width and with a specified accuracy of approximation for circular arcs, and using a specified end cap style.

Mathematically-exact buffer area boundaries can contain circular arcs. To represent these arcs using linear geometry they must be approximated with line segments. The <code>quadrantSegments</code> argument allows controlling the accuracy of the approximation by specifying the number of line segments used to represent a quadrant of a circle

The end cap style specifies the buffer geometry that will be created at the ends of linestrings. The styles provided are:

• <code>BufferOp.CAP_ROUND</code> - (default) a semi-circle

• <code>BufferOp.CAP_BUTT</code> - a straight line perpendicular to the end segment

• <code>BufferOp.CAP_SQUARE</code> - a half-square

The buffer operation always returns a polygonal result. The negative or zero-distance buffer of lines and points is always an empty {link Polygon}. This is also the result for the buffers of degenerate (zero-area) polygons.

Computes a buffer area around this geometry having the given width and with a specified accuracy of approximation for circular arcs.

Mathematically-exact buffer area boundaries can contain circular arcs. To represent these arcs using linear geometry they must be approximated with line segments. The <code>quadrantSegments</code> argument allows controlling the accuracy of the approximation by specifying the number of line segments used to represent a quadrant of a circle

The buffer operation always returns a polygonal result. The negative or zero-distance buffer of lines and points is always an empty {link Polygon}. This is also the result for the buffers of degenerate (zero-area) polygons.

Computes a buffer area around this geometry having the given width. The buffer of a Geometry is the Minkowski sum or difference of the geometry with a disc of radius <code>abs(distance)</code>.

Mathematically-exact buffer area boundaries can contain circular arcs. To represent these arcs using linear geometry they must be approximated with line segments. The buffer geometry is constructed using 8 segments per quadrant to approximate the circular arcs. The end cap style is <code>CAP_ROUND</code>.

The buffer operation always returns a polygonal result. The negative or zero-distance buffer of lines and points is always an empty {link Polygon}. This is also the result for the buffers of degenerate (zero-area) polygons.

Creates and returns a full copy of this {link GeometryCollection} object. (including all coordinates contained by it).

return a clone of this instance

Returns the first non-zero result of <code>compareTo</code> encountered as the two <code>Collection</code>s are iterated over. If, by the time one of the iterations is complete, no non-zero result has been encountered, returns 0 if the other iteration is also complete. If <code>b</code> completes before <code>a</code>, a positive number is returned; if a before b, a negative number.

Returns whether this <code>Geometry</code> is greater than, equal to, or less than another <code>Geometry</code>, using the given {link CoordinateSequenceComparator}.

<P>

If their classes are different, they are compared using the following ordering:

<UL> <LI> Point (lowest) <LI> MultiPoint <LI> LineString <LI> LinearRing <LI> MultiLineString <LI> Polygon <LI> MultiPolygon <LI> GeometryCollection (highest) </UL> If the two <code>Geometry</code>s have the same class, their first elements are compared. If those are the same, the second elements are compared, etc.

Returns whether this <code>Geometry</code> is greater than, equal to, or less than another <code>Geometry</code>. <P>

If their classes are different, they are compared using the following ordering:

<UL> <LI> Point (lowest) <LI> MultiPoint <LI> LineString <LI> LinearRing <LI> MultiLineString <LI> Polygon <LI> MultiPolygon <LI> GeometryCollection (highest) </UL> If the two <code>Geometry</code>s have the same class, their first elements are compared. If those are the same, the second elements are compared, etc.

Tests whether this geometry contains the argument geometry.

The <code>contains</code> predicate has the following equivalent definitions:

• Every point of the other geometry is a point of this geometry, and the interiors of the two geometries have at least one point in common.

• The DE-9IM Intersection Matrix for the two geometries matches the pattern <code>[T*****FF*]</code>

• <code>g.within(this) = true</code> <br>(<code>contains</code> is the converse of {link #within} )

An implication of the definition is that "Geometries do not contain their boundary". In other words, if a geometry A is a subset of the points in the boundary of a geometry B, <code>B.contains(A) = false</code>. (As a concrete example, take A to be a LineString which lies in the boundary of a Polygon B.) For a predicate with similar behaviour but avoiding this subtle limitation, see {link #covers}.

Computes the smallest convex <code>Polygon</code> that contains all the points in the <code>Geometry</code>. This obviously applies only to <code>Geometry</code> s which contain 3 or more points; the results for degenerate cases are specified as follows:

<TABLE> <TR> <TH> Number of <code>Point</code>s in argument <code>Geometry</code> </TH> <TH> <code>Geometry</code> class of result </TH> </TR> <TR> <TD> 0 </TD> <TD> empty <code>GeometryCollection</code> </TD> </TR> <TR> <TD> 1 </TD> <TD> <code>Point</code> </TD> </TR> <TR> <TD> 2 </TD> <TD> <code>LineString</code> </TD> </TR> <TR> <TD> 3 or more </TD> <TD> <code>Polygon</code> </TD> </TR> </TABLE>

return the minimum-area convex polygon containing this <code>Geometry</code>' s points

Creates a deep copy of this {link Geometry} object. Coordinate sequences contained in it are copied. All instance fields are copied (i.e. <code>envelope</code>, <tt>SRID</tt> and <tt>userData</tt>).

<b>NOTE:</b> the userData object reference (if present) is copied, but the value itself is not copied. If a deep copy is required this must be performed by the caller.

return a deep copy of this geometry

Tests whether this geometry is covered by the argument geometry.

The <code>coveredBy</code> predicate has the following equivalent definitions:

• Every point of this geometry is a point of the other geometry.

• The DE-9IM Intersection Matrix for the two geometries matches at least one of the following patterns:

• <code>[TFF]</code>

• <code>[TFF]</code>

• <code>[FTF]</code>

• <code>[FTF]</code>

• <code>g.covers(this) = true</code> <br>(<code>coveredBy</code> is the converse of {link #covers})

If either geometry is empty, the value of this predicate is <code>false</code>.

This predicate is similar to {link #within}, but is more inclusive (i.e. returns <code>true</code> for more cases).

Tests whether this geometry covers the argument geometry.

The <code>covers</code> predicate has the following equivalent definitions:

• Every point of the other geometry is a point of this geometry.

• The DE-9IM Intersection Matrix for the two geometries matches at least one of the following patterns:

• <code>[T*****FF*]</code>

• <code>[T**FF]</code>

• <code>[TFF]</code>

• <code>[**TFF]</code>

• <code>g.coveredBy(this) = true</code> <br>(<code>covers</code> is the converse of {link #coveredBy})

If either geometry is empty, the value of this predicate is <code>false</code>.

This predicate is similar to {link #contains}, but is more inclusive (i.e. returns <code>true</code> for more cases). In particular, unlike <code>contains</code> it does not distinguish between points in the boundary and in the interior of geometries. For most situations, <code>covers</code> should be used in preference to <code>contains</code>. As an added benefit, <code>covers</code> is more amenable to optimization, and hence should be more performant.

Tests whether this geometry crosses the argument geometry.

The <code>crosses</code> predicate has the following equivalent definitions:

• The geometries have some but not all interior points in common.

• The DE-9IM Intersection Matrix for the two geometries matches one of the following patterns:

• <code>[TT*****]</code> (for P/L, P/A, and L/A situations)

• <code>[T***T]</code> (for L/P, A/P, and A/L situations)

• <code>[0********]</code> (for L/L situations)

For any other combination of dimensions this predicate returns <code>false</code>.

The SFS defined this predicate only for P/L, P/A, L/L, and L/A situations. In order to make the relation symmetric, JTS extends the definition to apply to L/P, A/P and A/L situations as well.

Computes a <code>Geometry</code> representing the closure of the point-set of the points contained in this <code>Geometry</code> that are not contained in the <code>other</code> Geometry.

If the result is empty, it is an atomic geometry with the dimension of the left-hand input.

Non-empty {link GeometryCollection} arguments are not supported.

Tests whether this geometry is disjoint from the argument geometry.

The <code>disjoint</code> predicate has the following equivalent definitions:

• The two geometries have no point in common

• The DE-9IM Intersection Matrix for the two geometries matches <code>[FFFF***]</code>

• <code>! g.intersects(this) = true</code> <br>(<code>disjoint</code> is the inverse of <code>intersects</code>)

Returns the minimum distance between this <code>Geometry</code> and another <code>Geometry</code>.

Tests whether this geometry is structurally and numerically equal to a given <code>Object</code>. If the argument <code>Object</code> is not a <code>Geometry</code>, the result is <code>false</code>. Otherwise, the result is computed using {link #equalsExact(Geometry)}.

This method is provided to fulfill the Java contract for value-based object equality. In conjunction with {link #hashCode()} it provides semantics which are most useful for using <code>Geometry</code>s as keys and values in Java collections.

Note that to produce the expected result the input geometries should be in normal form. It is the caller's responsibility to perform this where required (using {link Geometry#norm()} or {link #normalize()} as appropriate).

Tests whether this geometry is topologically equal to the argument geometry.

This method is included for backward compatibility reasons. It has been superseded by the {link #equalsTopo(Geometry)} method, which has been named to clearly denote its functionality.

This method should NOT be confused with the method {link #equals(Object)}, which implements an exact equality comparison.

Returns true if the two <code>Geometry</code>s are exactly equal. Two Geometries are exactly equal iff:

• they have the same structure

• they have the same values for their vertices, in exactly the same order.

This provides a stricter test of equality than {link #equalsTopo(Geometry)}, which is more useful in certain situations (such as using geometries as keys in collections).

This method does <i>not</i> test the values of the <code>GeometryFactory</code>, the <code>SRID</code>, or the <code>userData</code> fields.

To properly test equality between different geometries, it is usually necessary to {link #normalize()} them first.

Tests whether two geometries are exactly equal in their normalized forms. This is a convenience method which creates normalized versions of both geometries before computing {link #equalsExact(Geometry)}.

This method is relatively expensive to compute. For maximum performance, the client should instead perform normalization on the individual geometries at an appropriate point during processing.

Tests whether this geometry is topologically equal to the argument geometry as defined by the SFS <code>equals</code> predicate.

The SFS <code>equals</code> predicate has the following equivalent definitions:

• The two geometries have at least one point in common, and no point of either geometry lies in the exterior of the other geometry.

• The DE-9IM Intersection Matrix for the two geometries matches the pattern <code>TF**FFF</code>

<pre> T*F **F FF* </pre>

<b>Note</b> that this method computes <b>topologically equality</b>. For structural equality, see {link #equalsExact(Geometry)}.

Notifies this geometry that its coordinates have been changed by an external party (for example, via a {link CoordinateFilter}). When this method is called the geometry will flush and/or update any derived information it has cached (such as its {link Envelope} ). The operation is applied to all component Geometries.

Returns the area of this <code>GeometryCollection</code>

return the area of the polygon

Computes the centroid of this <code>Geometry</code>. The centroid is equal to the centroid of the set of component Geometries of highest dimension (since the lower-dimension geometries contribute zero "weight" to the centroid).

The centroid of an empty geometry is <code>POINT EMPTY</code>.

return a { @link Point} which is the centroid of this Geometry

Collects all coordinates of all subgeometries into an Array.

Note that while changes to the coordinate objects themselves may modify the Geometries in place, the returned Array as such is only a temporary container which is not synchronized back.

return the collected coordinates

Gets a Geometry representing the envelope (bounding box) of this <code>Geometry</code>.

If this <code>Geometry</code> is:

• empty, returns an empty <code>Point</code>.

• a point, returns a <code>Point</code>.

• a line parallel to an axis, a two-vertex <code>LineString</code>

• otherwise, returns a <code>Polygon</code> whose vertices are (minx miny, maxx miny, maxx maxy, minx maxy, minx miny).

return a Geometry representing the envelope of this Geometry

Gets an {link Envelope} containing the minimum and maximum x and y values in this <code>Geometry</code>. If the geometry is empty, an empty <code>Envelope</code> is returned.

The returned object is a copy of the one maintained internally, to avoid aliasing issues. For best performance, clients which access this envelope frequently should cache the return value.

return the envelope of this <code>Geometry</code>. return an empty Envelope if this Geometry is empty

Gets the factory which contains the context in which this geometry was created.

return the factory for this geometry

Computes an interior point of this <code>Geometry</code>. An interior point is guaranteed to lie in the interior of the Geometry, if it possible to calculate such a point exactly. Otherwise, the point may lie on the boundary of the geometry.

The interior point of an empty geometry is <code>POINT EMPTY</code>.

return a { @link Point} which is in the interior of this Geometry

Returns the <code>PrecisionModel</code> used by the <code>Geometry</code>.

return the specification of the grid of allowable points, for this <code>Geometry</code> and all other <code>Geometry</code>s

Returns the ID of the Spatial Reference System used by the <code>Geometry</code>.

<P>

JTS supports Spatial Reference System information in the simple way defined in the SFS. A Spatial Reference System ID (SRID) is present in each <code>Geometry</code> object. <code>Geometry</code> provides basic accessor operations for this field, but no others. The SRID is represented as an integer.

return the ID of the coordinate space in which the <code>Geometry</code> is defined.

Gets the user data object for this geometry, if any.

return the user data object, or <code>null</code> if none set

Gets a hash code for the Geometry.

return an integer value suitable for use as a hashcode

Computes a <code>Geometry</code> representing the point-set which is common to both this <code>Geometry</code> and the <code>other</code> Geometry.

The intersection of two geometries of different dimension produces a result geometry of dimension less than or equal to the minimum dimension of the input geometries. The result geometry may be a heterogeneous {link GeometryCollection}. If the result is empty, it is an atomic geometry with the dimension of the lowest input dimension.

Intersection of {link GeometryCollection}s is supported only for homogeneous collection types.

Non-empty heterogeneous {link GeometryCollection} arguments are not supported.

Tests whether this geometry intersects the argument geometry.

The <code>intersects</code> predicate has the following equivalent definitions:

• The two geometries have at least one point in common

• The DE-9IM Intersection Matrix for the two geometries matches at least one of the patterns

• <code>[T********]</code>

• <code>[T******]</code>

• <code>[T**]</code>

• <code>[T]</code>

• <code>! g.disjoint(this) = true</code> <br>(<code>intersects</code> is the inverse of <code>disjoint</code>)

Tests whether this is a rectangular {link Polygon}.

return true if the geometry is a rectangle.

Tests whether this {link Geometry} is simple. The SFS definition of simplicity follows the general rule that a Geometry is simple if it has no points of self-tangency, self-intersection or other anomalous points.

Simplicity is defined for each {link Geometry} subclass as follows:

• Valid polygonal geometries are simple, since their rings must not self-intersect. <code>isSimple</code> tests for this condition and reports <code>false</code> if it is not met. (This is a looser test than checking for validity).

• Linear rings have the same semantics.

• Linear geometries are simple iff they do not self-intersect at points other than boundary points.

• Zero-dimensional geometries (points) are simple iff they have no repeated points.

• Empty <code>Geometry</code>s are always simple.

return <code>true</code> if this <code>Geometry</code> is simple

Tests whether this <code>Geometry</code> is topologically valid, according to the OGC SFS specification.

For validity rules see the Javadoc for the specific Geometry subclass.

return <code>true</code> if this <code>Geometry</code> is valid

Tests whether the distance from this <code>Geometry</code> to another is less than or equal to a specified value.

Creates a new Geometry which is a normalized copy of this Geometry.

return a normalized copy of this geometry.

Tests whether this geometry overlaps the specified geometry.

The <code>overlaps</code> predicate has the following equivalent definitions:

• The geometries have at least one point each not shared by the other (or equivalently neither covers the other), they have the same dimension, and the intersection of the interiors of the two geometries has the same dimension as the geometries themselves.

• The DE-9IM Intersection Matrix for the two geometries matches <code>[TTT]</code> (for two points or two surfaces) or <code>[1TT]</code> (for two curves)

If the geometries are of different dimension this predicate returns <code>false</code>. This predicate is symmetric.

Returns the DE-9IM {link IntersectionMatrix} for the two <code>Geometry</code>s.

Tests whether the elements in the DE-9IM {link IntersectionMatrix} for the two <code>Geometry</code>s match the elements in <code>intersectionPattern</code>. The pattern is a 9-character string, with symbols drawn from the following set:

<UL> <LI> 0 (dimension 0) <LI> 1 (dimension 1) <LI> 2 (dimension 2) <LI> T ( matches 0, 1 or 2) <LI> F ( matches FALSE) <LI> * ( matches any value) </UL> For more information on the DE-9IM, see the <i>OpenGIS Simple Features Specification</i>.

Sets the ID of the Spatial Reference System used by the <code>Geometry</code>.

<b>NOTE:</b> This method should only be used for exceptional circumstances or for backwards compatibility. Normally the SRID should be set on the {link GeometryFactory} used to create the geometry. SRIDs set using this method will <i>not</i> be propagated to geometries returned by constructive methods.

A simple scheme for applications to add their own custom data to a Geometry. An example use might be to add an object representing a Coordinate Reference System.

Note that user data objects are not present in geometries created by construction methods.

Computes a <code>Geometry </code> representing the closure of the point-set which is the union of the points in this <code>Geometry</code> which are not contained in the <code>other</code> Geometry, with the points in the <code>other</code> Geometry not contained in this <code>Geometry</code>. If the result is empty, it is an atomic geometry with the dimension of the highest input dimension.

Non-empty {link GeometryCollection} arguments are not supported.

Tests whether this geometry touches the argument geometry.

The <code>touches</code> predicate has the following equivalent definitions:

• The geometries have at least one point in common, but their interiors do not intersect.

• The DE-9IM Intersection Matrix for the two geometries matches at least one of the following patterns

• <code>[FT*******]</code>

• <code>[FT***]</code>

• <code>[F*T**]</code>

If both geometries have dimension 0, the predicate returns <code>false</code>, since points have only interiors. This predicate is symmetric.

Computes the union of all the elements of this geometry.

This method supports {link GeometryCollection}s (which the other overlay operations currently do not).

The result obeys the following contract:

• Unioning a set of {link LineString}s has the effect of fully noding and dissolving the linework.

• Unioning a set of {link Polygon}s always returns a {link Polygonal} geometry (unlike {link #union(Geometry)}, which may return geometries of lower dimension if a topology collapse occurred).

return the union geometry throws TopologyException if a robustness error occurs

Computes a <code>Geometry</code> representing the point-set which is contained in both this <code>Geometry</code> and the <code>other</code> Geometry.

The union of two geometries of different dimension produces a result geometry of dimension equal to the maximum dimension of the input geometries. The result geometry may be a heterogeneous {link GeometryCollection}. If the result is empty, it is an atomic geometry with the dimension of the highest input dimension.

Unioning {link LineString}s has the effect of <b>noding</b> and <b>dissolving</b> the input linework. In this context "noding" means that there will be a node or endpoint in the result for every endpoint or line segment crossing in the input. "Dissolving" means that any duplicate (i.e. coincident) line segments or portions of line segments will be reduced to a single line segment in the result. If <b>merged</b> linework is required, the {link LineMerger} class can be used.

Non-empty {link GeometryCollection} arguments are not supported.

Tests whether this geometry is within the specified geometry.

The <code>within</code> predicate has the following equivalent definitions:

• Every point of this geometry is a point of the other geometry, and the interiors of the two geometries have at least one point in common.

• The DE-9IM Intersection Matrix for the two geometries matches <code>[TFF]</code>

• <code>g.contains(this) = true</code> <br>(<code>within</code> is the converse of {link #contains})

An implication of the definition is that "The boundary of a Geometry is not within the Geometry". In other words, if a geometry A is a subset of the points in the boundary of a geometry B, <code>A.within(B) = false</code> (As a concrete example, take A to be a LineString which lies in the boundary of a Polygon B.) For a predicate with similar behaviour but avoiding this subtle limitation, see {link #coveredBy}.