GeneralPath
class represents a geometric path
constructed from straight lines, and quadratic and cubic
(Bézier) curves. It can contain multiple subpaths.
The winding rule specifies how the interior of a path is determined. There are two types of winding rules: EVEN_ODD and NON_ZERO.
An EVEN_ODD winding rule means that enclosed regions of the path alternate between interior and exterior areas as traversed from the outside of the path towards a point inside the region.
A NON_ZERO winding rule means that if a ray is drawn in any direction from a given point to infinity and the places where the path intersects the ray are examined, the point is inside of the path if and only if the number of times that the path crosses the ray from left to right does not equal the number of times that the path crosses the ray from right to left.
GeneralPath
object.
If an operation performed on this path requires the
interior of the path to be defined then the default NON_ZERO
winding rule is used.GeneralPath
object with the specified
winding rule to control operations that require the interior of the
path to be defined.GeneralPath
object with the specified
winding rule and the specified initial capacity to store path
coordinates. This number is an initial guess as to how many path
segments are in the path, but the storage is expanded
as needed to store whatever path segments are added to this path.GeneralPath
object from an arbitrary
Shape
object.
All of the initial geometry and the winding rule for this path are
taken from the specified Shape
object.connect
parameter is true
and the
path is not empty then any initial moveTo
in the
geometry of the appended Shape
is turned into a
lineTo
segment.
If the destination coordinates of such a connecting lineTo
segment match the ending coordinates of a currently open
subpath then the segment is omitted as superfluous.
The winding rule of the specified Shape
is ignored
and the appended geometry is governed by the winding
rule specified for this path.Shape
object to the
path, possibly connecting the new geometry to the existing path
segments with a line segment.
If the connect
parameter is true
and the
path is not empty then any initial moveTo
in the
geometry of the appended Shape
is turned into a lineTo
segment.
If the destination coordinates of such a connecting lineTo
segment match the ending coordinates of a currently open
subpath then the segment is omitted as superfluous.
The winding rule of the specified Shape
is ignored
and the appended geometry is governed by the winding
rule specified for this path.moveTo
. If the path is already
closed then this method has no effect.Shape
.Shape
entirely contains
the specified rectangular area. All coordinates that lie inside
the rectangular area must lie within the Shape
for the
entire rectanglar area to be considered contained within the
Shape
.
This method might conservatively return false
when:
intersect
method returns true
and
Shape
entirely contains the rectangular area are
prohibitively expensive.
false
even
though the Shape
contains the rectangular area.
The Area
class can be used to perform more accurate
computations of geometric intersection for any Shape
object if a more precise answer is required.Shape
.Shape
entirely contains the
specified Rectangle2D
.
This method might conservatively return false
when:
intersect
method returns true
and
Shape
entirely contains the Rectangle2D
are prohibitively expensive.
false
even
though the Shape
contains the
Rectangle2D
.
The Area
class can be used to perform more accurate
computations of geometric intersection for any Shape
object if a more precise answer is required.Shape
.
The equals
method implements an equivalence relation
on non-null object references:
x
, x.equals(x)
should return
true
.
x
and y
, x.equals(y)
should return true
if and only if
y.equals(x)
returns true
.
x
, y
, and z
, if
x.equals(y)
returns true
and
y.equals(z)
returns true
, then
x.equals(z)
should return true
.
x
and y
, multiple invocations of
x.equals(y) consistently return true
or consistently return false
, provided no
information used in equals
comparisons on the
objects is modified.
x
,
x.equals(null)
should return false
.
The equals method for class Object
implements
the most discriminating possible equivalence relation on objects;
that is, for any non-null reference values x
and
y
, this method returns true
if and only
if x
and y
refer to the same object
(x == y
has the value true
).
Note that it is generally necessary to override the hashCode method whenever this method is overridden, so as to maintain the general contract for the hashCode method, which states that equal objects must have equal hash codes.
Shape
. Note that there is no guarantee that the
returned Rectangle
is the smallest bounding box that
encloses the Shape
, only that the Shape
lies entirely within the indicated Rectangle
. The
returned Rectangle
might also fail to completely
enclose the Shape
if the Shape
overflows
the limited range of the integer data type. The
getBounds2D
method generally returns a
tighter bounding box due to its greater flexibility in
representation.Shape
than the getBounds
method.
Note that there is no guarantee that the returned
Rectangle2D
is the smallest bounding box that encloses
the Shape
, only that the Shape
lies
entirely within the indicated Rectangle2D
. The
bounding box returned by this method is usually tighter than that
returned by the getBounds
method and never fails due
to overflow problems since the return value can be an instance of
the Rectangle2D
that uses double precision values to
store the dimensions.Shape
boundary and provides access to the geometry of the
Shape
outline. If an optional AffineTransform
is specified, the coordinates returned in the iteration are
transformed accordingly.
Each call to this method returns a fresh PathIterator
object that traverses the geometry of the Shape
object
independently from any other PathIterator
objects in use
at the same time.
It is recommended, but not guaranteed, that objects
implementing the Shape
interface isolate iterations
that are in process from any changes that might occur to the original
object's geometry during such iterations.
Before using a particular implementation of the Shape
interface in more than one thread simultaneously, refer to its
documentation to verify that it guarantees that iterations are isolated
from modifications.
Shape
boundary and provides access to a flattened view of the
Shape
outline geometry.
Only SEG_MOVETO, SEG_LINETO, and SEG_CLOSE point types are returned by the iterator.
If an optional AffineTransform
is specified,
the coordinates returned in the iteration are transformed
accordingly.
The amount of subdivision of the curved segments is controlled
by the flatness
parameter, which specifies the
maximum distance that any point on the unflattened transformed
curve can deviate from the returned flattened path segments.
Note that a limit on the accuracy of the flattened path might be
silently imposed, causing very small flattening parameters to be
treated as larger values. This limit, if there is one, is
defined by the particular implementation that is used.
Each call to this method returns a fresh PathIterator
object that traverses the Shape
object geometry
independently from any other PathIterator
objects in use at
the same time.
It is recommended, but not guaranteed, that objects
implementing the Shape
interface isolate iterations
that are in process from any changes that might occur to the original
object's geometry during such iterations.
Before using a particular implementation of this interface in more than one thread simultaneously, refer to its documentation to verify that it guarantees that iterations are isolated from modifications.
java.util.Hashtable
.
The general contract of hashCode
is:
hashCode
method on each of
the two objects must produce the same integer result.
As much as is reasonably practical, the hashCode method defined by class Object does return distinct integers for distinct objects. (This is typically implemented by converting the internal address of the object into an integer, but this implementation technique is not required by the JavaTM programming language.)
Shape
intersects the
interior of a specified rectangular area.
The rectangular area is considered to intersect the Shape
if any point is contained in both the interior of the
Shape
and the specified rectangular area.
This method might conservatively return true
when:
Shape
intersect, but
true
even
though the rectangular area does not intersect the Shape
.
The Area
class can be used to perform
more accurate computations of geometric intersection for any
Shape
object if a more precise answer is required.Shape
intersects the
interior of a specified Rectangle2D
.
This method might conservatively return true
when:
Rectangle2D
and the
Shape
intersect, but
true
even
though the Rectangle2D
does not intersect the
Shape
.wait
methods.
The awakened thread will not be able to proceed until the current thread relinquishes the lock on this object. The awakened thread will compete in the usual manner with any other threads that might be actively competing to synchronize on this object; for example, the awakened thread enjoys no reliable privilege or disadvantage in being the next thread to lock this object.
This method should only be called by a thread that is the owner of this object's monitor. A thread becomes the owner of the object's monitor in one of three ways:
synchronized
statement
that synchronizes on the object.
Class,
by executing a
synchronized static method of that class.
Only one thread at a time can own an object's monitor.
wait
methods.
The awakened threads will not be able to proceed until the current thread relinquishes the lock on this object. The awakened threads will compete in the usual manner with any other threads that might be actively competing to synchronize on this object; for example, the awakened threads enjoy no reliable privilege or disadvantage in being the next thread to lock this object.
This method should only be called by a thread that is the owner
of this object's monitor. See the notify
method for a
description of the ways in which a thread can become the owner of
a monitor.
toString
method returns a string that
"textually represents" this object. The result should
be a concise but informative representation that is easy for a
person to read.
It is recommended that all subclasses override this method.
The toString
method for class Object
returns a string consisting of the name of the class of which the
object is an instance, the at-sign character `@
', and
the unsigned hexadecimal representation of the hash code of the
object. In other words, this method returns a string equal to the
value of:
getClass().getName() + '@' + Integer.toHexString(hashCode())
The current thread must own this object's monitor. The thread
releases ownership of this monitor and waits until another thread
notifies threads waiting on this object's monitor to wake up
either through a call to the notify
method or the
notifyAll
method. The thread then waits until it can
re-obtain ownership of the monitor and resumes execution.
As in the one argument version, interrupts and spurious wakeups are possible, and this method should always be used in a loop:
synchronized (obj) { while (<condition does not hold>) obj.wait(); ... // Perform action appropriate to condition }This method should only be called by a thread that is the owner of this object's monitor. See the
notify
method for a
description of the ways in which a thread can become the owner of
a monitor.The current thread must own this object's monitor.
This method causes the current thread (call it T) to place itself in the wait set for this object and then to relinquish any and all synchronization claims on this object. Thread T becomes disabled for thread scheduling purposes and lies dormant until one of four things happens:
A thread can also wake up without being notified, interrupted, or timing out, a so-called spurious wakeup. While this will rarely occur in practice, applications must guard against it by testing for the condition that should have caused the thread to be awakened, and continuing to wait if the condition is not satisfied. In other words, waits should always occur in loops, like this one:
synchronized (obj) { while (<condition does not hold>) obj.wait(timeout); ... // Perform action appropriate to condition }(For more information on this topic, see Section 3.2.3 in Doug Lea's "Concurrent Programming in Java (Second Edition)" (Addison-Wesley, 2000), or Item 50 in Joshua Bloch's "Effective Java Programming Language Guide" (Addison-Wesley, 2001).
If the current thread is interrupted by another thread while it is waiting, then an InterruptedException is thrown. This exception is not thrown until the lock status of this object has been restored as described above.
Note that the wait method, as it places the current thread into the wait set for this object, unlocks only this object; any other objects on which the current thread may be synchronized remain locked while the thread waits.
This method should only be called by a thread that is the owner
of this object's monitor. See the notify
method for a
description of the ways in which a thread can become the owner of
a monitor.
This method is similar to the wait
method of one
argument, but it allows finer control over the amount of time to
wait for a notification before giving up. The amount of real time,
measured in nanoseconds, is given by:
1000000*timeout+nanos
In all other respects, this method does the same thing as the method of one argument. In particular, wait(0, 0) means the same thing as wait(0).
The current thread must own this object's monitor. The thread releases ownership of this monitor and waits until either of the following two conditions has occurred:
notify
method
or the notifyAll
method.
timeout
milliseconds plus nanos
nanoseconds arguments, has
elapsed.
The thread then waits until it can re-obtain ownership of the monitor and resumes execution.
As in the one argument version, interrupts and spurious wakeups are possible, and this method should always be used in a loop:
synchronized (obj) { while (<condition does not hold>) obj.wait(timeout, nanos); ... // Perform action appropriate to condition }This method should only be called by a thread that is the owner of this object's monitor. See the
notify
method for a
description of the ways in which a thread can become the owner of
a monitor.