if (expression.equals(expr)) {
            int index = expr.indexOf("${");
            if (index >= 0) {
                int lastIndex = expr.indexOf('}', index);
                if (lastIndex >= 0) {
                    String retVal = expr.substring(0, index);

                    if ((index > 0) && (expr.charAt(index - 1) == '$')) {
                        retVal += expr.substring(index + 1, lastIndex + 1);
                    } else {

import java.util.List;
import java.util.Map;

import org.apache.maven.lifecycle.internal.builder.BuilderCommon;
import org.apache.maven.project.MavenProject;

/**
 * <p>
 * Provides the positional index of the project
 * </p>
 * <strong>NOTE:</strong> This class is not part of any public api and can be changed or deleted without prior notice.
 *
 * @since 3.0
 */

        } else {
            locations = new LinkedHashMap<>();
            for (int index : indices) {
                InputLocation location;
                if (index < 0) {
                    location = sourceLocations.get(~index);
                } else {
                    location = targetLocations.get(index);
                }
                locations.put(locations.size(), location);
            }

    }

    /**
     * Append content to the message buffer.
     *
     * @param value the content to append
     * @param start the starting index of the subsequence to be appended
     * @param end the end index of the subsequence to be appended
     * @return the current builder
     */
    @Nonnull
    default MessageBuilder a(CharSequence value, int start, int end) {

     *            {@link Severity#ERROR}.
     * @param source The source of the problem, may be {@code null}.
     * @param lineNumber The one-based index of the line containing the error or {@code -1} if unknown.
     * @param columnNumber The one-based index of the column containing the error or {@code -1} if unknown.
     * @param exception The exception that caused this problem, may be {@code null}.
     */

     *            {@link ModelProblem.Severity#ERROR}.
     * @param source The source of the problem, may be {@code null}.
     * @param lineNumber The one-based index of the line containing the error or {@code -1} if unknown.
     * @param columnNumber The one-based index of the column containing the error or {@code -1} if unknown.
     * @param exception The exception that caused this problem, may be {@code null}.
     */

     * @param source A hint about the source of the problem like a file path, may be {@code null}.
     * @param lineNumber The one-based index of the line containing the problem or {@code -1} if unknown.
     * @param columnNumber The one-based index of the column containing the problem or {@code -1} if unknown.
     * @param exception The exception that caused this problem, may be {@code null}.
     */
    DefaultProblem(

        }

        @Override
        public void add(int index, V element) {
            asList().add(index, element);
        }

        @Override
        public V remove(int index) {
            return asList().remove(index);
        }

        @Override
        public V get(int index) {
            return asList().get(index);
        }

        @Override
        public int size() {

                InputLocation location;
                Integer index = it.next();
                if (index.intValue() < 0) {
                    location = sourceLocations.get(Integer.valueOf(~index.intValue()));
                } else {
                    location = targetLocations.get(index);
                }
                locations.put(Integer.valueOf(locations.size()), location);

     * @param message The detail message of the problem, may be {@code null}.
     * @param line The one-based index of the line containing the problem or {@code -1} if unknown.
     * @param column The one-based index of the column containing the problem or {@code -1} if unknown.
     * @param cause The cause of the problem, may be {@code null}.
     */