Method resolveAmbiguousWrapper

java/jakarta/el/Util.java:303–361

(Set<Wrapper<T>> candidates, Class<?>[] paramTypes)

     * This method duplicates code in org.apache.el.util.ReflectionUtil. When making changes keep the code in sync.
     */
    private static <T> Wrapper<T> resolveAmbiguousWrapper(Set<Wrapper<T>> candidates, Class<?>[] paramTypes) {
        // Identify which parameter isn't an exact match
        Wrapper<T> w = candidates.iterator().next();

        int nonMatchIndex = 0;
        Class<?> nonMatchClass = null;

        for (int i = 0; i < paramTypes.length; i++) {
            if (w.getParameterTypes()[i] != paramTypes[i]) {
                nonMatchIndex = i;
                nonMatchClass = paramTypes[i];
                break;
            }
        }

        if (nonMatchClass == null) {
            // Null will always be ambiguous
            return null;
        }

        for (Wrapper<T> c : candidates) {
            if (c.getParameterTypes()[nonMatchIndex] == paramTypes[nonMatchIndex]) {
                // Methods have different non-matching parameters
                // Result is ambiguous
                return null;
            }
        }

        // Can't be null
        Class<?> superClass = nonMatchClass.getSuperclass();
        while (superClass != null) {
            for (Wrapper<T> c : candidates) {
                if (c.getParameterTypes()[nonMatchIndex].equals(superClass)) {
                    // Found a match
                    return c;
                }
            }
            superClass = superClass.getSuperclass();
        }

        // Treat instances of Number as a special case
        Wrapper<T> match = null;
        if (Number.class.isAssignableFrom(nonMatchClass)) {
            for (Wrapper<T> c : candidates) {
                Class<?> candidateType = c.getParameterTypes()[nonMatchIndex];
                if (Number.class.isAssignableFrom(candidateType) || candidateType.isPrimitive()) {
                    if (match == null) {
                        match = c;
                    } else {
                        // Match still ambiguous
                        match = null;
                        break;
                    }
                }
            }
        }

        return match;