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package cgeo.geocaching.test;
import cgeo.geocaching.test.mock.GC1ZXX2;
import cgeo.geocaching.test.mock.GC2CJPF;
import cgeo.geocaching.test.mock.GC2JVEH;
import cgeo.geocaching.test.mock.GC3XX5J;
import cgeo.geocaching.test.mock.MockedCache;
import cgeo.geocaching.utils.TextUtils;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.regex.Pattern;
import junit.framework.TestCase;
/**
* Test class to compare the performance of two regular expressions on given data.
* Can be used to improve the time needed to parse the cache data.
* Run As "JUnit Test"
*/
public class RegExPerformanceTest extends TestCase {
// Regular expression: "<img.*src=(\S*)/>"
// Input string 1: "<img border=1 src=image.jpg />"
// Input string 2: "<img src=src=src=src= .... many src= ... src=src="
// "a(.*)a", it's much better to use "a([^a]*)a".
// The rewritten expression "<img((?!src=).)*src=(\S*)/>" will handle a large, non-matching string almost a hundred times faster then the previous one!
/** Search until the start of the next tag. The tag can follow immediately */
public static final String NEXT_START_TAG = "[^<]*";
/** Search until the end of the actual tag. The closing tag can follow immediately */
public static final String NEXT_END_TAG = "[^>]*";
/** Search until the start of the next tag. The tag must not follow immediately */
public static final String NEXT_START_TAG2 = "[^<]+";
/** Search until the end of the actual tag. The closing tag must not follow immediately */
public static final String NEXT_END_TAG2 = "[^>]+";
/** P tag */
public static final String TAG_P_START = "<p>";
/** Closing P tag **/
public static final String TAG_P_END = "</p>";
/** Search until the next <p> */
public static final String TAG_P_START_NEXT = NEXT_START_TAG + TAG_P_START;
/** Search until the next </p> */
public static final String TAG_P_END_NEXT = NEXT_START_TAG + TAG_P_END;
/** strong tag */
public static final String TAG_STRONG_START = "<strong>";
/** Closing strong tag */
public static final String TAG_STRONG_END = "</strong>";
/** Search until the next <strong> */
public static final String TAG_STRONG_START_NEXT = NEXT_START_TAG + TAG_STRONG_START;
/** Search until the next </strong> */
public static final String TAG_STRONG_END_NEXT = NEXT_START_TAG + TAG_STRONG_END;
/** div tag */
public static final String TAG_DIV_START = "<div>";
/** closing div tag */
public static final String TAG_DIV_END = "</div>";
/** Search until the next <div> */
public static final String TAG_DIV_START_NEXT = NEXT_START_TAG + TAG_DIV_START;
/** Search until the next </div> */
public static final String TAG_DIV_END_NEXT = NEXT_START_TAG + TAG_DIV_END;
public final static Pattern PATTERN_DESCRIPTION_OLD = Pattern.compile("<span id=\"ctl00_ContentBody_LongDescription\"[^>]*>" + "(.*)</span>[^<]*</div>[^<]*<p>[^<]*</p>[^<]*<p>[^<]*<strong>\\W*Additional Hints</strong>", Pattern.CASE_INSENSITIVE);
public final static Pattern PATTERN_DESCRIPTION = Pattern.compile("<span id=\"ctl00_ContentBody_LongDescription\">(.*?)</span>[^<]*</div>[^<]*<p>[^<]*</p>[^<]*<p>[^<]*<strong>\\W*Additional Hints</strong>");
public final static List<MockedCache> MOCKED_CACHES;
static {
MOCKED_CACHES = Arrays.asList(new GC2CJPF(), new GC1ZXX2(), new GC2JVEH(), new GC3XX5J());
}
public static void testRegEx() {
final List<String> output = doTheTests(10);
for (String s : output) {
System.out.println(s);
}
}
public static List<String> doTheTests(final int iterations) {
final List<String> output = new ArrayList<String>();
output.addAll(measure(iterations, "description", PATTERN_DESCRIPTION_OLD, PATTERN_DESCRIPTION));
return output;
}
private static List<String> measure(int iterations, String fieldName, Pattern p1, Pattern p2) {
final List<String> output = new ArrayList<String>();
output.add(fieldName + ":");
for (MockedCache cache : MOCKED_CACHES) {
String page = cache.getData();
String result1 = TextUtils.getMatch(page, p1, true, "");
String result2 = TextUtils.getMatch(page, p2, true, "");
assertEquals(result1, result2);
long diff1, diff2;
output.add("Parsing " + cache.getGeocode() + " " + cache.getName());
diff1 = parse(page, p1, iterations);
output.add("Time pattern 1:\t" + diff1 + " ms");
diff2 = parse(page, p2, iterations);
output.add("Time pattern 2:\t" + diff2 + " ms");
float reduction = (float) diff2 * 100 / diff1;
output.add("New runtime:\t" + String.format("%.1f", reduction) + "%\n");
}
return output;
}
private static long parse(String page, Pattern pattern, int iterations) {
final long start = System.currentTimeMillis();
for (int j = 0; j < iterations; j++) {
TextUtils.getMatch(page, pattern, true, "");
}
return System.currentTimeMillis() - start;
}
}
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