85 long period = 0;
86
87 /**
88 * Creates a new timer task.
89 */
90 protected TimerTask() {
91 }
92
93 /**
94 * The action to be performed by this timer task.
95 */
96 public abstract void run();
97
98 /**
99 * Cancels this timer task. If the task has been scheduled for one-time
100 * execution and has not yet run, or has not yet been scheduled, it will
101 * never run. If the task has been scheduled for repeated execution, it
102 * will never run again. (If the task is running when this call occurs,
103 * the task will run to completion, but will never run again.)
104 *
105 * <p>Note that calling this method from within the <tt>run</tt> method of
106 * a repeating timer task absolutely guarantees that the timer task will
107 * not run again.
108 *
109 * <p>This method may be called repeatedly; the second and subsequent
110 * calls have no effect.
111 *
112 * @return true if this task is scheduled for one-time execution and has
113 * not yet run, or this task is scheduled for repeated execution.
114 * Returns false if the task was scheduled for one-time execution
115 * and has already run, or if the task was never scheduled, or if
116 * the task was already cancelled. (Loosely speaking, this method
117 * returns <tt>true</tt> if it prevents one or more scheduled
118 * executions from taking place.)
119 */
120 public boolean cancel() {
121 synchronized(lock) {
122 boolean result = (state == SCHEDULED);
123 state = CANCELLED;
124 return result;
125 }
126 }
127
128 /**
129 * Returns the <i>scheduled</i> execution time of the most recent
130 * <i>actual</i> execution of this task. (If this method is invoked
131 * while task execution is in progress, the return value is the scheduled
132 * execution time of the ongoing task execution.)
133 *
134 * <p>This method is typically invoked from within a task's run method, to
135 * determine whether the current execution of the task is sufficiently
136 * timely to warrant performing the scheduled activity:
137 * <pre>{@code
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85 long period = 0;
86
87 /**
88 * Creates a new timer task.
89 */
90 protected TimerTask() {
91 }
92
93 /**
94 * The action to be performed by this timer task.
95 */
96 public abstract void run();
97
98 /**
99 * Cancels this timer task. If the task has been scheduled for one-time
100 * execution and has not yet run, or has not yet been scheduled, it will
101 * never run. If the task has been scheduled for repeated execution, it
102 * will never run again. (If the task is running when this call occurs,
103 * the task will run to completion, but will never run again.)
104 *
105 * <p>Note that calling this method from within the {@code run} method of
106 * a repeating timer task absolutely guarantees that the timer task will
107 * not run again.
108 *
109 * <p>This method may be called repeatedly; the second and subsequent
110 * calls have no effect.
111 *
112 * @return true if this task is scheduled for one-time execution and has
113 * not yet run, or this task is scheduled for repeated execution.
114 * Returns false if the task was scheduled for one-time execution
115 * and has already run, or if the task was never scheduled, or if
116 * the task was already cancelled. (Loosely speaking, this method
117 * returns {@code true} if it prevents one or more scheduled
118 * executions from taking place.)
119 */
120 public boolean cancel() {
121 synchronized(lock) {
122 boolean result = (state == SCHEDULED);
123 state = CANCELLED;
124 return result;
125 }
126 }
127
128 /**
129 * Returns the <i>scheduled</i> execution time of the most recent
130 * <i>actual</i> execution of this task. (If this method is invoked
131 * while task execution is in progress, the return value is the scheduled
132 * execution time of the ongoing task execution.)
133 *
134 * <p>This method is typically invoked from within a task's run method, to
135 * determine whether the current execution of the task is sufficiently
136 * timely to warrant performing the scheduled activity:
137 * <pre>{@code
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