TailorHelper.java

package org.springframework.roo.addon.tailor.util;

import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang3.StringUtils;
import org.springframework.roo.addon.tailor.CommandTransformation;
import org.springframework.roo.addon.tailor.actions.ActionConfig;

/**
 * Helper static operations.
 * 
 * @author Birgitta Boeckeler
 * @author Vladimir Tihomirov
 */
public class TailorHelper {

  /**
   * Pattern to look for ${xxx} usage in a command string
   */
  private static final Pattern VAR_PATTERN = Pattern.compile("\\$\\{([\\w\\*]*)\\}");

  public static void removeComment(final CommentedLine commentedLine) {
    String line = commentedLine.getLine();
    boolean inBlockComment = commentedLine.getInBlockComment();
    if (StringUtils.isBlank(line)) {
      return;
    }
    if (line.contains("/*")) {
      inBlockComment = true;
      final String lhs = line.substring(0, line.lastIndexOf("/*"));
      if (line.contains("*/")) {
        line = lhs + line.substring(line.lastIndexOf("*/") + 2);
        inBlockComment = false;
      } else {
        line = lhs;
      }
    } else if (inBlockComment && line.contains("*/")) {
      line = line.substring(line.lastIndexOf("*/") + 2);
      inBlockComment = false;
    } else if (inBlockComment) {
      line = "";
    } else if (line.trim().startsWith("//") || line.trim().startsWith("#")) {
      line = "";
    }
    commentedLine.setLine(line.replace('\t', ' '));
    commentedLine.setInBlockComment(inBlockComment);
  }

  /**
   * Looks for ${xxx} pattern in {@link ActionConfig#getCommand()} and
   * replaces those placeholders with the respective values from the
   * inputCommand's arguments.
   * 
   * @param trafo The CommandTransformation instance with the inputCommand to
   *            use to extract the values
   * @param text A string with potential occurrences of placeholders
   * @return The new command string
   */
  public static String replaceVars(final CommandTransformation trafo, String text) {
    /*
     * TODO: This could also be done the other way around: iterate over all
     * arguments of the input command and replace the corresponding ${}
     * occurrences. >> Think about which makes more sense.
     */
    final Map<String, String> inputArguments = trafo.getArguments();
    if (inputArguments == null || inputArguments.isEmpty()) {
      return text;
    }

    final Matcher matcher = VAR_PATTERN.matcher(text);
    while (matcher.find()) {
      // Placeholder name between ${}
      final String placeholder = matcher.group(1);
      String inputValue = null;
      if ("*".equals(placeholder)) {
        // In this case, take the last fragment of the original command
        // that is not defined with "--" > assumed this is the first
        // argument,
        // which can sometimes be given without a "--" name
        final String[] split = inputArguments.get("").split(" ");
        inputValue = split[split.length - 1];
      } else {
        inputValue = inputArguments.get(placeholder);
      }
      if (inputValue != null) {
        // Escape the special characters to ensure correct replacement
        String replace = matcher.group().replace("$", "\\$");
        replace = replace.replace("{", "\\{");
        replace = replace.replace("}", "\\}");
        replace = replace.replace("*", "\\*");
        // Do the actual replacement
        text = text.replaceAll(replace, inputValue);
      }
    }
    return text;
  }
}