BasicStroke
class defines a basic set of rendering
attributes for the outlines of graphics primitives, which are rendered
with a Graphics2D
object that has its Stroke attribute set to
this BasicStroke
.
The rendering attributes defined by BasicStroke
describe
the shape of the mark made by a pen drawn along the outline of a
Shape
and the decorations applied at the ends and joins of
path segments of the Shape
.
These rendering attributes include:
Shape
argument. When a Graphics2D
object uses a
Stroke
object to redefine a path during the execution
of one of its draw
methods, the geometry is supplied
in its original form before the Graphics2D
transform
attribute is applied. Therefore, attributes such as the pen width
are interpreted in the user space coordinate system of the
Graphics2D
object and are subject to the scaling and
shearing effects of the user-space-to-device-space transform in that
particular Graphics2D
.
For example, the width of a rendered shape's outline is determined
not only by the width attribute of this BasicStroke
,
but also by the transform attribute of the
Graphics2D
object. Consider this code:
// sets the Graphics2D object's Tranform attribute g2d.scale(10, 10); // sets the Graphics2D object's Stroke attribute g2d.setStroke(new BasicStroke(1.5f));Assuming there are no other scaling transforms added to the
Graphics2D
object, the resulting line
will be approximately 15 pixels wide.
As the example code demonstrates, a floating-point line
offers better precision, especially when large transforms are
used with a Graphics2D
object.
When a line is diagonal, the exact width depends on how the
rendering pipeline chooses which pixels to fill as it traces the
theoretical widened outline. The choice of which pixels to turn
on is affected by the antialiasing attribute because the
antialiasing rendering pipeline can choose to color
partially-covered pixels.
For more information on the user space coordinate system and the
rendering process, see the Graphics2D
class comments.
BasicStroke
with the specified
attributes.BasicStroke
with the specified
attributes.BasicStroke
with the specified
attributes. The miterlimit
parameter is
unnecessary in cases where the default is allowable or the
line joins are not specified as JOIN_MITER.BasicStroke
with the specified
line width and with default values for the cap and join
styles.BasicStroke
with defaults for all
attributes.
The default attributes are a solid line of width 1.0, CAP_SQUARE,
JOIN_MITER, a miter limit of 10.0.Shape
which encloses the area that
should be painted when the Shape
is stroked according
to the rules defined by the
object implementing the Stroke
interface.BasicStroke
by first testing if it is a BasicStroke
and then comparing
its width, join, cap, miter limit, dash, and dash phase attributes with
those of this BasicStroke
.Shape
to be stroked, the user space
distance that the pen travels is accumulated. The distance
value is used to index into the dash array.
The pen is opaque when its current cumulative distance maps
to an even element of the dash array and transparent otherwise.Graphics2D
class comments for more information on
the user space coordinate system.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.