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SciJava Common is a shared library for SciJava software. It provides a plugin framework, with an extensible mechanism for service discovery, backed by its own annotation processor, so that plugins can be loaded dynamically. It is used by downstream projects in the SciJava ecosystem, such as ImageJ and SCIFIO.
/*
* #%L
* SciJava Common shared library for SciJava software.
* %%
* Copyright (C) 2009 - 2014 Board of Regents of the University of
* Wisconsin-Madison, Broad Institute of MIT and Harvard, and Max Planck
* Institute of Molecular Cell Biology and Genetics.
* %%
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
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*/
package org.scijava.util;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.Map.Entry;
/**
* A helper class to help with optimizing the performance of a list of
* operations.
*
* For example, when trying to figure out which
* {@link org.scijava.service.Service} would be the best candidate to speed up
* {@link org.scijava.Context} initialization, this helper comes in real handy:
* it accumulates a list of operations with their duration and prints out a
* sorted list when asked to.
*
*
* Use this class as following:
*
*
* private static Timing timing = new Timing();
* ...
* private void oneOperation() {
* final long t1 = System.nanoTime();
* ...
* timing.add(System.nanoTime() - t1, "Operation #1");
* }
* ...
* private void atEnd() {
* ...
* timing.report("Operations");
* }
*
*
* @author Johannes Schindelin
*/
public class Timing {
private long total = 0, start = System.nanoTime(), tick = start;
private List> list = new ArrayList>();
public void reset() {
tick = System.nanoTime();
}
public void addTiming(final Object message) {
addTiming(System.nanoTime() - tick, message == null ? getCaller() : message);
tick = System.nanoTime();
}
public void addTiming(final long duration, final Object message) {
final long now = System.nanoTime();
total += duration;
list.add(new Entry() {
@Override
public Long getKey() {
return Long.valueOf(duration);
}
@Override
public String getValue() {
return message.toString() + ": " + ((now - start - duration) / 1e6) + " - " + ((now - start) / 1e6);
}
@Override
public String setValue(String value) {
throw new UnsupportedOperationException();
}
});
}
public void report(final String description) {
System.err.println(description == null ? getCaller() : description);
Collections.sort(list, new Comparator>() {
@Override
public int compare(Entry o1,
Entry o2) {
return Double.compare(o1.getKey(), o2.getKey());
}
});
for (final Entry e: list) {
System.err.printf("% 5.3f ms %s\n", ((Long)e.getKey()) / 1e6, e.getValue());
}
System.err.println("Total time: " + total + " = " + (total / 1e9) + " sec");
}
private static String getCaller() {
final StackTraceElement[] trace =
Thread.currentThread().getStackTrace();
int i = 1;
while (i + 1 < trace.length &&
Timing.class.getName().equals(trace[i].getClassName())) {
i++;
}
return i >= trace.length ? "?" : trace[i].getClassName() + "."
+ trace[i].getMethodName() + "(" + trace[i].getFileName() + ":"
+ trace[i].getLineNumber() + ")";
}
public static Timing start(boolean condition) {
return condition ? new Timing() : null;
}
public static void tick(final Timing timing) {
if (timing != null) timing.addTiming(null);
}
public static void tick(final Timing timing, final Object message) {
if (timing != null) timing.addTiming(message);
}
public static void stop(final Timing timing) {
if (timing == null) return;
timing.addTiming(null);
timing.report(null);
}
}