source: josm/trunk/src/org/openstreetmap/josm/gui/mappaint/mapcss/ExpressionFactory.java@ 7450

Last change on this file since 7450 was 7450, checked in by bastiK, 10 years ago

fixed #10421 - User-settings for mapcss mappaint styles

  • only boolean setting for now
  • no shortcut support so far
File size: 34.7 KB
Line 
1// License: GPL. For details, see LICENSE file.
2package org.openstreetmap.josm.gui.mappaint.mapcss;
3
4import java.awt.Color;
5import java.io.UnsupportedEncodingException;
6import java.lang.annotation.ElementType;
7import java.lang.annotation.Retention;
8import java.lang.annotation.RetentionPolicy;
9import java.lang.annotation.Target;
10import java.lang.reflect.Array;
11import java.lang.reflect.InvocationTargetException;
12import java.lang.reflect.Method;
13import java.net.URLEncoder;
14import java.nio.charset.StandardCharsets;
15import java.util.ArrayList;
16import java.util.Arrays;
17import java.util.Collection;
18import java.util.Collections;
19import java.util.List;
20import java.util.regex.Matcher;
21import java.util.regex.Pattern;
22import java.util.zip.CRC32;
23
24import org.openstreetmap.josm.Main;
25import org.openstreetmap.josm.actions.search.SearchCompiler;
26import org.openstreetmap.josm.actions.search.SearchCompiler.Match;
27import org.openstreetmap.josm.actions.search.SearchCompiler.ParseError;
28import org.openstreetmap.josm.data.osm.Node;
29import org.openstreetmap.josm.data.osm.OsmPrimitive;
30import org.openstreetmap.josm.gui.mappaint.Cascade;
31import org.openstreetmap.josm.gui.mappaint.Environment;
32import org.openstreetmap.josm.io.XmlWriter;
33import org.openstreetmap.josm.tools.ColorHelper;
34import org.openstreetmap.josm.tools.Predicates;
35import org.openstreetmap.josm.tools.RightAndLefthandTraffic;
36import org.openstreetmap.josm.tools.Utils;
37
38/**
39 * Factory to generate Expressions.
40 *
41 * See {@link #createFunctionExpression}.
42 */
43public final class ExpressionFactory {
44
45 /**
46 * Marks functions which should be executed also when one or more arguments are null.
47 */
48 @Target(ElementType.METHOD)
49 @Retention(RetentionPolicy.RUNTIME)
50 static @interface NullableArguments {}
51
52 private static final List<Method> arrayFunctions = new ArrayList<>();
53 private static final List<Method> parameterFunctions = new ArrayList<>();
54 private static final List<Method> parameterFunctionsEnv = new ArrayList<>();
55
56 static {
57 for (Method m : Functions.class.getDeclaredMethods()) {
58 Class<?>[] paramTypes = m.getParameterTypes();
59 if (paramTypes.length == 1 && paramTypes[0].isArray()) {
60 arrayFunctions.add(m);
61 } else if (paramTypes.length >= 1 && paramTypes[0].equals(Environment.class)) {
62 parameterFunctionsEnv.add(m);
63 } else {
64 parameterFunctions.add(m);
65 }
66 }
67 try {
68 parameterFunctions.add(Math.class.getMethod("abs", float.class));
69 parameterFunctions.add(Math.class.getMethod("acos", double.class));
70 parameterFunctions.add(Math.class.getMethod("asin", double.class));
71 parameterFunctions.add(Math.class.getMethod("atan", double.class));
72 parameterFunctions.add(Math.class.getMethod("atan2", double.class, double.class));
73 parameterFunctions.add(Math.class.getMethod("ceil", double.class));
74 parameterFunctions.add(Math.class.getMethod("cos", double.class));
75 parameterFunctions.add(Math.class.getMethod("cosh", double.class));
76 parameterFunctions.add(Math.class.getMethod("exp", double.class));
77 parameterFunctions.add(Math.class.getMethod("floor", double.class));
78 parameterFunctions.add(Math.class.getMethod("log", double.class));
79 parameterFunctions.add(Math.class.getMethod("max", float.class, float.class));
80 parameterFunctions.add(Math.class.getMethod("min", float.class, float.class));
81 parameterFunctions.add(Math.class.getMethod("random"));
82 parameterFunctions.add(Math.class.getMethod("round", float.class));
83 parameterFunctions.add(Math.class.getMethod("signum", double.class));
84 parameterFunctions.add(Math.class.getMethod("sin", double.class));
85 parameterFunctions.add(Math.class.getMethod("sinh", double.class));
86 parameterFunctions.add(Math.class.getMethod("sqrt", double.class));
87 parameterFunctions.add(Math.class.getMethod("tan", double.class));
88 parameterFunctions.add(Math.class.getMethod("tanh", double.class));
89 } catch (NoSuchMethodException | SecurityException ex) {
90 throw new RuntimeException(ex);
91 }
92 }
93
94 private ExpressionFactory() {
95 // Hide default constructor for utils classes
96 }
97
98 /**
99 * List of functions that can be used in MapCSS expressions.
100 *
101 * First parameter can be of type {@link Environment} (if needed). This is
102 * automatically filled in by JOSM and the user only sees the remaining
103 * arguments.
104 * When one of the user supplied arguments cannot be converted the
105 * expected type or is null, the function is not called and it returns null
106 * immediately. Add the annotation {@link NullableArguments} to allow
107 * null arguments.
108 * Every method must be static.
109 */
110 @SuppressWarnings("UnusedDeclaration")
111 public static class Functions {
112
113 /**
114 * Identity function for compatibility with MapCSS specification.
115 * @param o any object
116 * @return {@code o} unchanged
117 */
118 public static Object eval(Object o) {
119 return o;
120 }
121
122 public static float plus(float... args) {
123 float res = 0;
124 for (float f : args) {
125 res += f;
126 }
127 return res;
128 }
129
130 public static Float minus(float... args) {
131 if (args.length == 0) {
132 return 0.0F;
133 }
134 if (args.length == 1) {
135 return -args[0];
136 }
137 float res = args[0];
138 for (int i = 1; i < args.length; ++i) {
139 res -= args[i];
140 }
141 return res;
142 }
143
144 public static float times(float... args) {
145 float res = 1;
146 for (float f : args) {
147 res *= f;
148 }
149 return res;
150 }
151
152 public static Float divided_by(float... args) {
153 if (args.length == 0) {
154 return 1.0F;
155 }
156 float res = args[0];
157 for (int i = 1; i < args.length; ++i) {
158 if (args[i] == 0.0F) {
159 return null;
160 }
161 res /= args[i];
162 }
163 return res;
164 }
165
166 /**
167 * Creates a list of values, e.g., for the {@code dashes} property.
168 * @see Arrays#asList(Object[])
169 */
170 public static List<Object> list(Object... args) {
171 return Arrays.asList(args);
172 }
173
174 /**
175 * Returns the number of elements in a list.
176 * @param lst the list
177 * @return length of the list
178 */
179 public static Integer count(List<?> lst) {
180 return lst.size();
181 }
182
183 /**
184 * Returns the first non-null object. The name originates from the {@code COALESCE} SQL function.
185 * @deprecated Deprecated in favour of {@link #any(Object...)} from the MapCSS standard.
186 */
187 @NullableArguments
188 @Deprecated
189 public static Object coalesce(Object... args) {
190 return any(args);
191 }
192
193 /**
194 * Returns the first non-null object.
195 * The name originates from <a href="http://wiki.openstreetmap.org/wiki/MapCSS/0.2/eval">MapCSS standard</a>.
196 * @see #coalesce(Object...)
197 * @see Utils#firstNonNull(Object[])
198 */
199 @NullableArguments
200 public static Object any(Object... args) {
201 return Utils.firstNonNull(args);
202 }
203
204 /**
205 * Get the {@code n}th element of the list {@code lst} (counting starts at 0).
206 * @since 5699
207 */
208 public static Object get(List<?> lst, float n) {
209 int idx = Math.round(n);
210 if (idx >= 0 && idx < lst.size()) {
211 return lst.get(idx);
212 }
213 return null;
214 }
215
216 /**
217 * Splits string {@code toSplit} at occurrences of the separator string {@code sep} and returns a list of matches.
218 * @see String#split(String)
219 * @since 5699
220 */
221 public static List<String> split(String sep, String toSplit) {
222 return Arrays.asList(toSplit.split(Pattern.quote(sep), -1));
223 }
224
225 /**
226 * Creates a color value with the specified amounts of {@code r}ed, {@code g}reen, {@code b}lue (arguments from 0.0 to 1.0)
227 * @see Color#Color(float, float, float)
228 */
229 public static Color rgb(float r, float g, float b) {
230 try {
231 return new Color(r, g, b);
232 } catch (IllegalArgumentException e) {
233 return null;
234 }
235 }
236
237 public static Color rgba(float r, float g, float b, float alpha) {
238 try {
239 return new Color(r, g, b, alpha);
240 } catch (IllegalArgumentException e) {
241 return null;
242 }
243 }
244
245 /**
246 * Create color from hsb color model. (arguments form 0.0 to 1.0)
247 * @param h hue
248 * @param s saturation
249 * @param b brightness
250 * @return the corresponding color
251 */
252 public static Color hsb_color(float h, float s, float b) {
253 try {
254 return Color.getHSBColor(h, s, b);
255 } catch (IllegalArgumentException e) {
256 return null;
257 }
258 }
259
260 /**
261 * Creates a color value from an HTML notation, i.e., {@code #rrggbb}.
262 */
263 public static Color html2color(String html) {
264 return ColorHelper.html2color(html);
265 }
266
267 /**
268 * Computes the HTML notation ({@code #rrggbb}) for a color value).
269 */
270 public static String color2html(Color c) {
271 return ColorHelper.color2html(c);
272 }
273
274 /**
275 * Get the value of the red color channel in the rgb color model
276 * @return the red color channel in the range [0;1]
277 * @see java.awt.Color#getRed()
278 */
279 public static float red(Color c) {
280 return Utils.color_int2float(c.getRed());
281 }
282
283 /**
284 * Get the value of the green color channel in the rgb color model
285 * @return the green color channel in the range [0;1]
286 * @see java.awt.Color#getGreen()
287 */
288 public static float green(Color c) {
289 return Utils.color_int2float(c.getGreen());
290 }
291
292 /**
293 * Get the value of the blue color channel in the rgb color model
294 * @return the blue color channel in the range [0;1]
295 * @see java.awt.Color#getBlue()
296 */
297 public static float blue(Color c) {
298 return Utils.color_int2float(c.getBlue());
299 }
300
301 /**
302 * Get the value of the alpha channel in the rgba color model
303 * @return the alpha channel in the range [0;1]
304 * @see java.awt.Color#getAlpha()
305 */
306 public static float alpha(Color c) {
307 return Utils.color_int2float(c.getAlpha());
308 }
309
310 /**
311 * Assembles the strings to one.
312 * @see Utils#join
313 */
314 @NullableArguments
315 public static String concat(Object... args) {
316 return Utils.join("", Arrays.asList(args));
317 }
318
319 /**
320 * Assembles the strings to one, where the first entry is used as separator.
321 * @see Utils#join
322 */
323 @NullableArguments
324 public static String join(String... args) {
325 return Utils.join(args[0], Arrays.asList(args).subList(1, args.length));
326 }
327
328 /**
329 * Returns the value of the property {@code key}, e.g., {@code prop("width")}.
330 */
331 public static Object prop(final Environment env, String key) {
332 return prop(env, key, null);
333 }
334
335 /**
336 * Returns the value of the property {@code key} from layer {@code layer}.
337 */
338 public static Object prop(final Environment env, String key, String layer) {
339 return env.getCascade(layer).get(key);
340 }
341
342 /**
343 * Determines whether property {@code key} is set.
344 */
345 public static Boolean is_prop_set(final Environment env, String key) {
346 return is_prop_set(env, key, null);
347 }
348
349 /**
350 * Determines whether property {@code key} is set on layer {@code layer}.
351 */
352 public static Boolean is_prop_set(final Environment env, String key, String layer) {
353 return env.getCascade(layer).containsKey(key);
354 }
355
356 /**
357 * Gets the value of the key {@code key} from the object in question.
358 */
359 public static String tag(final Environment env, String key) {
360 return env.osm == null ? null : env.osm.get(key);
361 }
362
363 /**
364 * Gets the first non-null value of the key {@code key} from the object's parent(s).
365 */
366 public static String parent_tag(final Environment env, String key) {
367 if (env.parent == null) {
368 if (env.osm != null) {
369 // we don't have a matched parent, so just search all referrers
370 for (OsmPrimitive parent : env.osm.getReferrers()) {
371 String value = parent.get(key);
372 if (value != null) {
373 return value;
374 }
375 }
376 }
377 return null;
378 }
379 return env.parent.get(key);
380 }
381
382 public static String child_tag(final Environment env, String key) {
383 return env.child == null ? null : env.child.get(key);
384 }
385
386 /**
387 * Determines whether the object has a tag with the given key.
388 */
389 public static boolean has_tag_key(final Environment env, String key) {
390 return env.osm.hasKey(key);
391 }
392
393 /**
394 * Returns the index of node in parent way or member in parent relation.
395 */
396 public static Float index(final Environment env) {
397 if (env.index == null) {
398 return null;
399 }
400 return new Float(env.index + 1);
401 }
402
403 public static String role(final Environment env) {
404 return env.getRole();
405 }
406
407 public static boolean not(boolean b) {
408 return !b;
409 }
410
411 public static boolean greater_equal(float a, float b) {
412 return a >= b;
413 }
414
415 public static boolean less_equal(float a, float b) {
416 return a <= b;
417 }
418
419 public static boolean greater(float a, float b) {
420 return a > b;
421 }
422
423 public static boolean less(float a, float b) {
424 return a < b;
425 }
426
427 /**
428 * Determines if the objects {@code a} and {@code b} are equal.
429 * @see Object#equals(Object)
430 */
431 public static boolean equal(Object a, Object b) {
432 if (a.getClass() == b.getClass()) return a.equals(b);
433 if (a.equals(Cascade.convertTo(b, a.getClass()))) return true;
434 return b.equals(Cascade.convertTo(a, b.getClass()));
435 }
436
437 /**
438 * Determines whether the JOSM search with {@code searchStr} applies to the object.
439 */
440 public static Boolean JOSM_search(final Environment env, String searchStr) {
441 Match m;
442 try {
443 m = SearchCompiler.compile(searchStr, false, false);
444 } catch (ParseError ex) {
445 return null;
446 }
447 return m.match(env.osm);
448 }
449
450 /**
451 * Obtains the JOSM'key {@link org.openstreetmap.josm.data.Preferences} string for key {@code key},
452 * and defaults to {@code def} if that is null.
453 * @see org.openstreetmap.josm.data.Preferences#get(String, String)
454 */
455 public static String JOSM_pref(String key, String def) {
456 String res = Main.pref.get(key, null);
457 return res != null ? res : def;
458 }
459
460 /**
461 * Tests if string {@code target} matches pattern {@code pattern}
462 * @see Pattern#matches(String, CharSequence)
463 * @since 5699
464 */
465 public static boolean regexp_test(String pattern, String target) {
466 return Pattern.matches(pattern, target);
467 }
468
469 /**
470 * Tests if string {@code target} matches pattern {@code pattern}
471 * @param flags a string that may contain "i" (case insensitive), "m" (multiline) and "s" ("dot all")
472 * @since 5699
473 */
474 public static boolean regexp_test(String pattern, String target, String flags) {
475 int f = 0;
476 if (flags.contains("i")) {
477 f |= Pattern.CASE_INSENSITIVE;
478 }
479 if (flags.contains("s")) {
480 f |= Pattern.DOTALL;
481 }
482 if (flags.contains("m")) {
483 f |= Pattern.MULTILINE;
484 }
485 return Pattern.compile(pattern, f).matcher(target).matches();
486 }
487
488 /**
489 * Tries to match string against pattern regexp and returns a list of capture groups in case of success.
490 * The first element (index 0) is the complete match (i.e. string).
491 * Further elements correspond to the bracketed parts of the regular expression.
492 * @param flags a string that may contain "i" (case insensitive), "m" (multiline) and "s" ("dot all")
493 * @since 5701
494 */
495 public static List<String> regexp_match(String pattern, String target, String flags) {
496 int f = 0;
497 if (flags.contains("i")) {
498 f |= Pattern.CASE_INSENSITIVE;
499 }
500 if (flags.contains("s")) {
501 f |= Pattern.DOTALL;
502 }
503 if (flags.contains("m")) {
504 f |= Pattern.MULTILINE;
505 }
506 Matcher m = Pattern.compile(pattern, f).matcher(target);
507 return Utils.getMatches(m);
508 }
509
510 /**
511 * Tries to match string against pattern regexp and returns a list of capture groups in case of success.
512 * The first element (index 0) is the complete match (i.e. string).
513 * Further elements correspond to the bracketed parts of the regular expression.
514 * @since 5701
515 */
516 public static List<String> regexp_match(String pattern, String target) {
517 Matcher m = Pattern.compile(pattern).matcher(target);
518 return Utils.getMatches(m);
519 }
520
521 /**
522 * Returns the OSM id of the current object.
523 * @see OsmPrimitive#getUniqueId()
524 */
525 public static long osm_id(final Environment env) {
526 return env.osm.getUniqueId();
527 }
528
529 /**
530 * Translates some text for the current locale. The first argument is the text to translate,
531 * and the subsequent arguments are parameters for the string indicated by {@code {0}}, {@code {1}}, …
532 */
533 @NullableArguments
534 public static String tr(String... args) {
535 final String text = args[0];
536 System.arraycopy(args, 1, args, 0, args.length - 1);
537 return org.openstreetmap.josm.tools.I18n.tr(text, (Object[])args);
538 }
539
540 /**
541 * Returns the substring of {@code s} starting at index {@code begin} (inclusive, 0-indexed).
542 * @param s The base string
543 * @param begin The start index
544 * @return the substring
545 * @see String#substring(int)
546 */
547 public static String substring(String s, /* due to missing Cascade.convertTo for int*/ float begin) {
548 return s == null ? null : s.substring((int) begin);
549 }
550
551 /**
552 * Returns the substring of {@code s} starting at index {@code begin} (inclusive)
553 * and ending at index {@code end}, (exclusive, 0-indexed).
554 * @param s The base string
555 * @param begin The start index
556 * @param end The end index
557 * @return the substring
558 * @see String#substring(int, int)
559 */
560 public static String substring(String s, float begin, float end) {
561 return s == null ? null : s.substring((int) begin, (int) end);
562 }
563
564 /**
565 * Replaces in {@code s} every {@code} target} substring by {@code replacement}.
566 * * @see String#replace(CharSequence, CharSequence)
567 */
568 public static String replace(String s, String target, String replacement) {
569 return s == null ? null : s.replace(target, replacement);
570 }
571
572 /**
573 * Percent-encode a string. (See https://en.wikipedia.org/wiki/Percent-encoding)
574 * This is especially useful for data urls, e.g.
575 * <code>icon-image: concat("data:image/svg+xml,", URL_encode("&lt;svg&gt;...&lt;/svg&gt;"));</code>
576 * @param s arbitrary string
577 * @return the encoded string
578 */
579 public static String URL_encode(String s) {
580 try {
581 return s == null ? null : URLEncoder.encode(s, "UTF-8");
582 } catch (UnsupportedEncodingException ex) {
583 throw new RuntimeException(ex);
584 }
585 }
586
587 /**
588 * XML-encode a string.
589 *
590 * Escapes special characters in xml. Alternative to using &lt;![CDATA[ ... ]]&gt; blocks.
591 * @param s arbitrary string
592 * @return the encoded string
593 */
594 public static String XML_encode(String s) {
595 return s == null ? null : XmlWriter.encode(s);
596 }
597
598 /**
599 * Calculates the CRC32 checksum from a string (based on RFC 1952).
600 * @param s the string
601 * @return long value from 0 to 2^32-1
602 */
603 public static long CRC32_checksum(String s) {
604 CRC32 cs = new CRC32();
605 cs.update(s.getBytes(StandardCharsets.UTF_8));
606 return cs.getValue();
607 }
608
609 /**
610 * check if there is right-hand traffic at the current location
611 * @param env the environment
612 * @return true if there is right-hand traffic
613 * @since 7193
614 */
615 public static boolean is_right_hand_traffic(Environment env) {
616 if (env.osm instanceof Node)
617 return RightAndLefthandTraffic.isRightHandTraffic(((Node) env.osm).getCoor());
618 return RightAndLefthandTraffic.isRightHandTraffic(env.osm.getBBox().getCenter());
619 }
620
621 /**
622 * Prints the object to the command line (for debugging purpose).
623 * @param o the object
624 * @return the same object, unchanged
625 */
626 @NullableArguments
627 public static Object print(Object o) {
628 System.out.print(o == null ? "none" : o.toString());
629 return o;
630 }
631
632 /**
633 * Prints the object to the command line, with new line at the end
634 * (for debugging purpose).
635 * @param o the object
636 * @return the same object, unchanged
637 */
638 @NullableArguments
639 public static Object println(Object o) {
640 System.out.println(o == null ? "none" : o.toString());
641 return o;
642 }
643
644 /**
645 * Get the number of tags for the current primitive.
646 * @param env the environment
647 * @return number of tags
648 */
649 public static int number_of_tags(Environment env) {
650 return env.osm.getNumKeys();
651 }
652
653 /**
654 * Get value of a setting.
655 * @param env the environment
656 * @param key setting key (given as layer identifier, e.g. setting::mykey {...})
657 * @return the value of the setting (calculated when the style is loaded)
658 */
659 public static Object setting(Environment env, String key) {
660 return env.source.settingValues.get(key);
661 }
662 }
663
664 /**
665 * Main method to create an function-like expression.
666 *
667 * @param name the name of the function or operator
668 * @param args the list of arguments (as expressions)
669 * @return the generated Expression. If no suitable function can be found,
670 * returns {@link NullExpression#INSTANCE}.
671 */
672 public static Expression createFunctionExpression(String name, List<Expression> args) {
673 if ("cond".equals(name) && args.size() == 3)
674 return new CondOperator(args.get(0), args.get(1), args.get(2));
675 else if ("and".equals(name))
676 return new AndOperator(args);
677 else if ("or".equals(name))
678 return new OrOperator(args);
679 else if ("length".equals(name) && args.size() == 1)
680 return new LengthFunction(args.get(0));
681 else if ("max".equals(name) && !args.isEmpty())
682 return new MinMaxFunction(args, true);
683 else if ("min".equals(name) && !args.isEmpty())
684 return new MinMaxFunction(args, false);
685
686 for (Method m : arrayFunctions) {
687 if (m.getName().equals(name))
688 return new ArrayFunction(m, args);
689 }
690 for (Method m : parameterFunctions) {
691 if (m.getName().equals(name) && args.size() == m.getParameterTypes().length)
692 return new ParameterFunction(m, args, false);
693 }
694 for (Method m : parameterFunctionsEnv) {
695 if (m.getName().equals(name) && args.size() == m.getParameterTypes().length-1)
696 return new ParameterFunction(m, args, true);
697 }
698 return NullExpression.INSTANCE;
699 }
700
701 /**
702 * Expression that always evaluates to null.
703 */
704 public static class NullExpression implements Expression {
705
706 /**
707 * The unique instance.
708 */
709 public static final NullExpression INSTANCE = new NullExpression();
710
711 @Override
712 public Object evaluate(Environment env) {
713 return null;
714 }
715 }
716
717 /**
718 * Conditional operator.
719 */
720 public static class CondOperator implements Expression {
721
722 private Expression condition, firstOption, secondOption;
723
724 public CondOperator(Expression condition, Expression firstOption, Expression secondOption) {
725 this.condition = condition;
726 this.firstOption = firstOption;
727 this.secondOption = secondOption;
728 }
729
730 @Override
731 public Object evaluate(Environment env) {
732 Boolean b = Cascade.convertTo(condition.evaluate(env), boolean.class);
733 if (b != null && b)
734 return firstOption.evaluate(env);
735 else
736 return secondOption.evaluate(env);
737 }
738 }
739
740 public static class AndOperator implements Expression {
741
742 private List<Expression> args;
743
744 public AndOperator(List<Expression> args) {
745 this.args = args;
746 }
747
748 @Override
749 public Object evaluate(Environment env) {
750 for (Expression arg : args) {
751 Boolean b = Cascade.convertTo(arg.evaluate(env), boolean.class);
752 if (b == null || !b) {
753 return false;
754 }
755 }
756 return true;
757 }
758 }
759
760 public static class OrOperator implements Expression {
761
762 private List<Expression> args;
763
764 public OrOperator(List<Expression> args) {
765 this.args = args;
766 }
767
768 @Override
769 public Object evaluate(Environment env) {
770 for (Expression arg : args) {
771 Boolean b = Cascade.convertTo(arg.evaluate(env), boolean.class);
772 if (b != null && b) {
773 return true;
774 }
775 }
776 return false;
777 }
778 }
779
780 /**
781 * Function to calculate the length of a string or list in a MapCSS eval
782 * expression.
783 *
784 * Separate implementation to support overloading for different
785 * argument types.
786 *
787 * The use for calculating the length of a list is deprecated, use
788 * {@link Functions#count(java.util.List)} instead (see #10061).
789 */
790 public static class LengthFunction implements Expression {
791
792 private Expression arg;
793
794 public LengthFunction(Expression args) {
795 this.arg = args;
796 }
797
798 @Override
799 public Object evaluate(Environment env) {
800 List<?> l = Cascade.convertTo(arg.evaluate(env), List.class);
801 if (l != null)
802 return l.size();
803 String s = Cascade.convertTo(arg.evaluate(env), String.class);
804 if (s != null)
805 return s.length();
806 return null;
807 }
808 }
809
810 /**
811 * Computes the maximum/minimum value an arbitrary number of floats, or a list of floats.
812 */
813 public static class MinMaxFunction implements Expression {
814
815 private final List<Expression> args;
816 private final boolean computeMax;
817
818 public MinMaxFunction(final List<Expression> args, final boolean computeMax) {
819 this.args = args;
820 this.computeMax = computeMax;
821 }
822
823 public Float aggregateList(List<?> lst) {
824 final List<Float> floats = Utils.transform(lst, new Utils.Function<Object, Float>() {
825 @Override
826 public Float apply(Object x) {
827 return Cascade.convertTo(x, float.class);
828 }
829 });
830 final Collection<Float> nonNullList = Utils.filter(floats, Predicates.not(Predicates.isNull()));
831 return computeMax ? Collections.max(nonNullList) : Collections.min(nonNullList);
832 }
833
834 @Override
835 public Object evaluate(final Environment env) {
836 List<?> l = Cascade.convertTo(args.get(0).evaluate(env), List.class);
837 if (args.size() != 1 || l == null)
838 l = Utils.transform(args, new Utils.Function<Expression, Object>() {
839 @Override
840 public Object apply(Expression x) {
841 return x.evaluate(env);
842 }
843 });
844 return aggregateList(l);
845 }
846 }
847
848 /**
849 * Function that takes a certain number of argument with specific type.
850 *
851 * Implementation is based on a Method object.
852 * If any of the arguments evaluate to null, the result will also be null.
853 */
854 public static class ParameterFunction implements Expression {
855
856 private final Method m;
857 private final boolean nullable;
858 private final List<Expression> args;
859 private final Class<?>[] expectedParameterTypes;
860 private final boolean needsEnvironment;
861
862 public ParameterFunction(Method m, List<Expression> args, boolean needsEnvironment) {
863 this.m = m;
864 this.nullable = m.getAnnotation(NullableArguments.class) != null;
865 this.args = args;
866 this.expectedParameterTypes = m.getParameterTypes();
867 this.needsEnvironment = needsEnvironment;
868 }
869
870 @Override
871 public Object evaluate(Environment env) {
872 Object[] convertedArgs;
873
874 if (needsEnvironment) {
875 convertedArgs = new Object[args.size()+1];
876 convertedArgs[0] = env;
877 for (int i = 1; i < convertedArgs.length; ++i) {
878 convertedArgs[i] = Cascade.convertTo(args.get(i-1).evaluate(env), expectedParameterTypes[i]);
879 if (convertedArgs[i] == null && !nullable) {
880 return null;
881 }
882 }
883 } else {
884 convertedArgs = new Object[args.size()];
885 for (int i = 0; i < convertedArgs.length; ++i) {
886 convertedArgs[i] = Cascade.convertTo(args.get(i).evaluate(env), expectedParameterTypes[i]);
887 if (convertedArgs[i] == null && !nullable) {
888 return null;
889 }
890 }
891 }
892 Object result = null;
893 try {
894 result = m.invoke(null, convertedArgs);
895 } catch (IllegalAccessException | IllegalArgumentException ex) {
896 throw new RuntimeException(ex);
897 } catch (InvocationTargetException ex) {
898 Main.error(ex);
899 return null;
900 }
901 return result;
902 }
903
904 @Override
905 public String toString() {
906 StringBuilder b = new StringBuilder("ParameterFunction~");
907 b.append(m.getName()).append("(");
908 for (int i = 0; i < args.size(); ++i) {
909 if (i > 0) b.append(",");
910 b.append(expectedParameterTypes[i]);
911 b.append(" ").append(args.get(i));
912 }
913 b.append(')');
914 return b.toString();
915 }
916
917 }
918
919 /**
920 * Function that takes an arbitrary number of arguments.
921 *
922 * Currently, all array functions are static, so there is no need to
923 * provide the environment, like it is done in {@link ParameterFunction}.
924 * If any of the arguments evaluate to null, the result will also be null.
925 */
926 public static class ArrayFunction implements Expression {
927
928 private final Method m;
929 private final boolean nullable;
930 private final List<Expression> args;
931 private final Class<?>[] expectedParameterTypes;
932 private final Class<?> arrayComponentType;
933
934 public ArrayFunction(Method m, List<Expression> args) {
935 this.m = m;
936 this.nullable = m.getAnnotation(NullableArguments.class) != null;
937 this.args = args;
938 this.expectedParameterTypes = m.getParameterTypes();
939 this.arrayComponentType = expectedParameterTypes[0].getComponentType();
940 }
941
942 @Override
943 public Object evaluate(Environment env) {
944 Object[] convertedArgs = new Object[expectedParameterTypes.length];
945 Object arrayArg = Array.newInstance(arrayComponentType, args.size());
946 for (int i = 0; i < args.size(); ++i) {
947 Object o = Cascade.convertTo(args.get(i).evaluate(env), arrayComponentType);
948 if (o == null && !nullable) {
949 return null;
950 }
951 Array.set(arrayArg, i, o);
952 }
953 convertedArgs[0] = arrayArg;
954
955 Object result = null;
956 try {
957 result = m.invoke(null, convertedArgs);
958 } catch (IllegalAccessException | IllegalArgumentException ex) {
959 throw new RuntimeException(ex);
960 } catch (InvocationTargetException ex) {
961 Main.error(ex);
962 return null;
963 }
964 return result;
965 }
966 @Override
967 public String toString() {
968 StringBuilder b = new StringBuilder("ArrayFunction~");
969 b.append(m.getName()).append("(");
970 for (int i = 0; i < args.size(); ++i) {
971 if (i > 0) b.append(",");
972 b.append(arrayComponentType);
973 b.append(" ").append(args.get(i));
974 }
975 b.append(')');
976 return b.toString();
977 }
978
979 }
980
981}
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