/* * Janino - An embedded Java[TM] compiler * * Copyright (c) 2001-2010, Arno Unkrig * All rights reserved. * * 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. * 3. The name of the author may not be used to endorse or promote products derived from this software without * specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. */ package org.codehaus.janino.util; import java.util.Stack; /** * Implements a scheme for benchmarking, i.e. for determining and/or reporting the time elapsed * between the beginning and the end of an activity. *
* The measurement is done by invoking {@link #begin()} and later calling {@link #end()} whichs * returns the time elapsed since the call to {@link #begin()}. *
* Notice that calls to {@link #begin()} and {@link #end()} can be nested, and each call to * {@link #end()} refers to the matching {@link #begin()} call. To ensure that all calls match, * the preferred way to write a benchmark is *
* ... * Benchmark b = new Benchmark(); * ... * b.begin(); * try { * .... * } finally { * long ms = b.end(); * } ** This code layout also makes it visually easy to write correct pairs of {@link #begin()} / * {@link #end()} pairs. *
* The pair {@link #beginReporting()} and {@link #endReporting()} do basically the same, but
* report the benchmarking information through an internal {@link Reporter} object. The default
* {@link Reporter} prints its messages by System.out.println()
.
*
* Reporting is only enabled if the Benchmark object was created through {@link #Benchmark(boolean)}
* with a true
argument.
*/
@SuppressWarnings({ "rawtypes", "unchecked" }) public
class Benchmark {
private final Stack beginTimes = new Stack(); // Long
public
Benchmark() {
this.reportingEnabled = false;
this.reporter = null;
}
/** @see Benchmark */
public void
begin() { this.beginTimes.push(new Long(System.currentTimeMillis())); }
/** @see Benchmark */
public long
end() { return System.currentTimeMillis() - ((Long) this.beginTimes.pop()).longValue(); }
// Reporting-related methods and fields.
/** Sets up a {@link Benchmark} with a default {@link Reporter} that reports to {@code System.out}. */
public
Benchmark(boolean reportingEnabled) {
this.reportingEnabled = reportingEnabled;
this.reporter = new Reporter() {
@Override public void report(String message) { System.out.println(message); }
};
}
/** Set up a {@link Benchmark} with a custom {@link Reporter}. */
public
Benchmark(boolean reportingEnabled, Reporter reporter) {
this.reportingEnabled = reportingEnabled;
this.reporter = reporter;
}
private final boolean reportingEnabled;
private final Reporter reporter;
/** Interface used to report messages. */
public
interface Reporter {
/** Reports the given {@code message}. */
void report(String message);
}
/** Begin a benchmark (see {@link #begin()}) and report the fact. */
public void
beginReporting() {
if (!this.reportingEnabled) return;
this.reportIndented("Beginning...");
this.begin();
}
/** Begin a benchmark (see {@link #begin()}) and report the fact. */
public void
beginReporting(String message) {
if (!this.reportingEnabled) return;
this.reportIndented(message + "...");
this.begin();
}
/** End a benchmark (see {@link #end()}) and report the fact. */
public void
endReporting() {
if (!this.reportingEnabled) return;
this.reportIndented("... took " + this.end() + " ms");
}
/** End a benchmark (see {@link #begin()}) and report the fact. */
public void
endReporting(String message) {
if (!this.reportingEnabled) return;
this.reportIndented("... took " + this.end() + " ms: " + message);
}
/** Report the given message. */
public void
report(String message) {
if (!this.reportingEnabled) return;
this.reportIndented(message);
}
/**
* Report the title
, a colon, a space, and the pretty-printed
* {@link Object}.
* @param optionalTitle
* @param o
*/
public void
report(String optionalTitle, Object o) {
if (!this.reportingEnabled) return;
String prefix = optionalTitle == null ? "" : (
optionalTitle
+ ": "
+ (optionalTitle.length() < Benchmark.PAD.length() ? Benchmark.PAD.substring(optionalTitle.length()) : "")
);
if (o == null) {
this.reportIndented(prefix + "(undefined)");
} else
if (o.getClass().isArray()) {
Object[] oa = (Object[]) o;
if (oa.length == 0) {
this.reportIndented(prefix + "(empty)");
} else
if (oa.length == 1) {
this.reportIndented(prefix + oa[0].toString());
} else {
this.reportIndented(optionalTitle == null ? "Array:" : optionalTitle + ':');
this.begin();
try {
for (Object o2 : oa) this.report(null, o2);
} finally {
this.end();
}
}
} else
{
this.reportIndented(prefix + o.toString());
}
}
private static final String PAD = " ";
/** Report a message through {@link #reporter}, indent by N spaces where N is the current benchmark stack depth. */
private void
reportIndented(String message) {
StringBuilder sb = new StringBuilder();
for (int i = this.beginTimes.size(); i > 0; --i) sb.append(" ");
sb.append(message);
this.reporter.report(sb.toString());
}
}