public Object getValue(String expression) {
            Object value = valueSource.getValue(expression);

            if (value != null && expression.startsWith(bannedPrefix)) {
                String msg = "The expression ${" + expression + "} is deprecated.";
                if (newPrefix != null && !newPrefix.isEmpty()) {
                    msg += " Please use ${" + newPrefix + expression.substring(bannedPrefix.length()) + "} instead.";

  private interface Impossible {}

  /**
   * Ensures the truth of an expression involving one or more parameters to the calling method.
   *
   * @param expression a boolean expression
   * @throws IllegalArgumentException if {@code expression} is false
   */
  public static void checkArgument(boolean expression) {
    if (!expression) {
      throw new IllegalArgumentException();
    }
  }

  /**

            for (String expression : BASEDIR_EXPRESSIONS) {
                if (s.startsWith(expression)) {
                    basedirExpr = expression;
                    break;
                }
            }

            if (basedirExpr != null) {
                if (s.length() > basedirExpr.length()) {
                    // Take out basedir expression and the leading slash

     *            不正であってはならない引数の名前
     * @param expression
     *            事前条件
     * @param description
     *            不正な引数であることの説明
     * @throws ClIllegalArgumentException
     *             {@code expression}がfalseの場合。
     */
    public static void assertArgument(final String argName, final boolean expression, final String description) {
        if (!expression) {

import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException;
import org.codehaus.plexus.component.configurator.expression.TypeAwareExpressionEvaluator;

/**
 * Evaluator for plugin parameters expressions. Content surrounded by <code>${</code> and <code>}</code> is evaluated.
 * Recognized values are:
 * <table border="1">
 * <caption>Expression matrix</caption>

        if (basedir != null) {
            interpolator.addValueSource(new AbstractValueSource(false) {
                @Override
                public Object getValue(String expression) {
                    if ("basedir".equals(expression) || "project.basedir".equals(expression)) {
                        return basedir.toAbsolutePath().toString();
                    }
                    return null;
                }
            });

import org.codehaus.plexus.component.configurator.ConfigurationListener;
import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException;
import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluator;
import org.codehaus.plexus.component.repository.ComponentDescriptor;
import org.codehaus.plexus.component.repository.exception.ComponentLifecycleException;

  private interface Impossible {}

  /**
   * Ensures the truth of an expression involving one or more parameters to the calling method.
   *
   * @param expression a boolean expression
   * @throws IllegalArgumentException if {@code expression} is false
   */
  public static void checkArgument(boolean expression) {
    if (!expression) {
      throw new IllegalArgumentException();
    }
  }

  /**

        return boostExpression;
    }

    public void setBoostExpression(final String expression) {
        boostExpression = expression;
    }

    public String getMatchExpression() {
        return matchExpression;
    }

    public void setMatchExpression(final String expression) {
        matchExpression = expression;
    }

                    filters.add(new HighestVersionFilter(num));
                } else if ("l".equals(expression)) {
                    filters.add(new LowestVersionFilter());
                } else if (expression.startsWith("l(") && expression.endsWith(")")) {
                    int num = Integer.parseInt(expression.substring(2, expression.length() - 1));