public static Object evaluate()

in src/main/java/org/apache/maven/shared/utils/introspection/ReflectionValueExtractor.java [166:222]
46 lines of code
11 McCabe index (conditional complexity)

    public static Object evaluate(@Nonnull String expression, @Nullable Object root, boolean trimRootToken)
            throws IntrospectionException {
        Object value = root;

        // ----------------------------------------------------------------------
        // Walk the dots and retrieve the ultimate value desired from the
        // MavenProject instance.
        // ----------------------------------------------------------------------

        if (StringUtils.isEmpty(expression) || !Character.isJavaIdentifierStart(expression.charAt(0))) {
            return null;
        }

        boolean hasDots = expression.indexOf(PROPERTY_START) >= 0;

        final Tokenizer tokenizer;
        if (trimRootToken && hasDots) {
            tokenizer = new Tokenizer(expression);
            tokenizer.nextPropertyName();
            if (tokenizer.getPosition() == EOF) {
                return null;
            }
        } else {
            tokenizer = new Tokenizer("." + expression);
        }

        int propertyPosition = tokenizer.getPosition();
        while (value != null && tokenizer.peekChar() != EOF) {
            switch (tokenizer.skipChar()) {
                case INDEXED_START:
                    value = getIndexedValue(
                            expression,
                            propertyPosition,
                            tokenizer.getPosition(),
                            value,
                            tokenizer.nextToken(INDEXED_END));
                    break;
                case MAPPED_START:
                    value = getMappedValue(
                            expression,
                            propertyPosition,
                            tokenizer.getPosition(),
                            value,
                            tokenizer.nextToken(MAPPED_END));
                    break;
                case PROPERTY_START:
                    propertyPosition = tokenizer.getPosition();
                    value = getPropertyValue(value, tokenizer.nextPropertyName());
                    break;
                default:
                    // could not parse expression
                    return null;
            }
        }

        return value;
    }