Examples with MethodFilter org.springframework.expression.MethodFilter used on opensource projects

Example 1 with MethodFilter

use of org.springframework.expression.MethodFilter in project spring-framework by spring-projects.

the class ReflectiveMethodResolver method resolve.

/**
	 * Locate a method on a type. There are three kinds of match that might occur:
	 * <ol>
	 * <li>an exact match where the types of the arguments match the types of the constructor
	 * <li>an in-exact match where the types we are looking for are subtypes of those defined on the constructor
	 * <li>a match where we are able to convert the arguments into those expected by the constructor,
	 * according to the registered type converter
	 * </ol>
	 */
@Override
public MethodExecutor resolve(EvaluationContext context, Object targetObject, String name, List<TypeDescriptor> argumentTypes) throws AccessException {
    try {
        TypeConverter typeConverter = context.getTypeConverter();
        Class<?> type = (targetObject instanceof Class ? (Class<?>) targetObject : targetObject.getClass());
        List<Method> methods = new ArrayList<>(getMethods(type, targetObject));
        // If a filter is registered for this type, call it
        MethodFilter filter = (this.filters != null ? this.filters.get(type) : null);
        if (filter != null) {
            List<Method> filtered = filter.filter(methods);
            methods = (filtered instanceof ArrayList ? filtered : new ArrayList<>(filtered));
        }
        // Sort methods into a sensible order
        if (methods.size() > 1) {
            Collections.sort(methods, new Comparator<Method>() {

                @Override
                public int compare(Method m1, Method m2) {
                    int m1pl = m1.getParameterCount();
                    int m2pl = m2.getParameterCount();
                    // varargs methods go last
                    if (m1pl == m2pl) {
                        if (!m1.isVarArgs() && m2.isVarArgs()) {
                            return -1;
                        } else if (m1.isVarArgs() && !m2.isVarArgs()) {
                            return 1;
                        } else {
                            return 0;
                        }
                    }
                    return (m1pl < m2pl ? -1 : (m1pl > m2pl ? 1 : 0));
                }
            });
        }
        // Resolve any bridge methods
        for (int i = 0; i < methods.size(); i++) {
            methods.set(i, BridgeMethodResolver.findBridgedMethod(methods.get(i)));
        }
        // Remove duplicate methods (possible due to resolved bridge methods)
        Set<Method> methodsToIterate = new LinkedHashSet<>(methods);
        Method closeMatch = null;
        int closeMatchDistance = Integer.MAX_VALUE;
        Method matchRequiringConversion = null;
        boolean multipleOptions = false;
        for (Method method : methodsToIterate) {
            if (method.getName().equals(name)) {
                Class<?>[] paramTypes = method.getParameterTypes();
                List<TypeDescriptor> paramDescriptors = new ArrayList<>(paramTypes.length);
                for (int i = 0; i < paramTypes.length; i++) {
                    paramDescriptors.add(new TypeDescriptor(new MethodParameter(method, i)));
                }
                ReflectionHelper.ArgumentsMatchInfo matchInfo = null;
                if (method.isVarArgs() && argumentTypes.size() >= (paramTypes.length - 1)) {
                    // *sigh* complicated
                    matchInfo = ReflectionHelper.compareArgumentsVarargs(paramDescriptors, argumentTypes, typeConverter);
                } else if (paramTypes.length == argumentTypes.size()) {
                    // Name and parameter number match, check the arguments
                    matchInfo = ReflectionHelper.compareArguments(paramDescriptors, argumentTypes, typeConverter);
                }
                if (matchInfo != null) {
                    if (matchInfo.isExactMatch()) {
                        return new ReflectiveMethodExecutor(method);
                    } else if (matchInfo.isCloseMatch()) {
                        if (this.useDistance) {
                            int matchDistance = ReflectionHelper.getTypeDifferenceWeight(paramDescriptors, argumentTypes);
                            if (closeMatch == null || matchDistance < closeMatchDistance) {
                                // This is a better match...
                                closeMatch = method;
                                closeMatchDistance = matchDistance;
                            }
                        } else {
                            // Take this as a close match if there isn't one already
                            if (closeMatch == null) {
                                closeMatch = method;
                            }
                        }
                    } else if (matchInfo.isMatchRequiringConversion()) {
                        if (matchRequiringConversion != null) {
                            multipleOptions = true;
                        }
                        matchRequiringConversion = method;
                    }
                }
            }
        }
        if (closeMatch != null) {
            return new ReflectiveMethodExecutor(closeMatch);
        } else if (matchRequiringConversion != null) {
            if (multipleOptions) {
                throw new SpelEvaluationException(SpelMessage.MULTIPLE_POSSIBLE_METHODS, name);
            }
            return new ReflectiveMethodExecutor(matchRequiringConversion);
        } else {
            return null;
        }
    } catch (EvaluationException ex) {
        throw new AccessException("Failed to resolve method", ex);
    }
}

Example 2 with MethodFilter

use of org.springframework.expression.MethodFilter in project spring-framework by spring-projects.

the class EvaluationTests method customMethodFilter.

/**
	 * Verifies behavior requested in SPR-9621.
	 */
@Test
public void customMethodFilter() throws Exception {
    StandardEvaluationContext context = new StandardEvaluationContext();
    // Register a custom MethodResolver...
    List<MethodResolver> customResolvers = new ArrayList<>();
    customResolvers.add(new CustomMethodResolver());
    context.setMethodResolvers(customResolvers);
    // or simply...
    // context.setMethodResolvers(new ArrayList<MethodResolver>());
    // Register a custom MethodFilter...
    MethodFilter filter = new CustomMethodFilter();
    try {
        context.registerMethodFilter(String.class, filter);
        fail("should have failed");
    } catch (IllegalStateException ise) {
        assertEquals("Method filter cannot be set as the reflective method resolver is not in use", ise.getMessage());
    }
}