Method replaceVariablesInString

src/main/java/gate/Utils.java:1159–1244

This will replace all occurrences of variables of the form $env{name}, $prop{name}, $doc{featname}, $pr_parm{inputAS} or $$env{name} etc in a String. The source for replacing the variable can be environment variables, system properties, or arbitrary maps or resources specified when calling the met

(
          String string, Object... sources)

   *  
   */
  @SuppressWarnings("unchecked")
  public static String replaceVariablesInString(
          String string, Object... sources)
  {
    // shortcut for strings where no replacement is possible (minimum content 
    // would have to be $pr{x}
    if(string == null || string.isEmpty() || string.length() < 6) { return string; }
    Matcher matcher = varnamePattern.matcher(string);
    int findFrom = 0;
    int lastEnd = 0;
    StringBuilder sb = new StringBuilder(string.length()*2);
    while(findFrom < string.length() && matcher.find(findFrom)) {
      String dollars = matcher.group(1);
      String type = matcher.group(2);
      String varname = matcher.group(3);
      int matchStart = matcher.start();
      // whenever we have found something, we can immediately move the part
      // from the last end of match to the new start of match to the 
      // return string, that is just unmodified string ...
      // But only if the length is > 0
      if((matchStart - lastEnd) > 0) {
        sb.append(string.substring(lastEnd,matchStart));
      }
      lastEnd = matcher.end();
      Object value = null;
      // for each match we find, go through all the sources in the order
      // listed and if the type of the source matches the requested type
      // then try to look the variable up. If we find something use it and
      // finish looking, otherwise continue until all sources have been 
      // exhausted. 
      // A variable where no value has been found anywhere is not replaced.
      // If a variable got replaced and it was a variable that started with
      // two dollar signs, then the replacement value is first getting 
      // recursively replaced too.
      if(type.equals("env")) {
        value = System.getenv().get(varname);
      } else if(type.equals("prop")) {
        value = System.getProperties().get(varname);
      } else {
        for(Object source : sources) {
          if(type.isEmpty()) { // an empty variable type matches only maps from the sources
            if(source instanceof Map) {
              value = ((Map<String,?>)source).get(varname);
            }
          } else if(type.equals("pr") && (source instanceof ProcessingResource)) {
            value = ((FeatureBearer)source).getFeatures().get(varname);
          } else if(type.equals("pr_parm") && (source instanceof ProcessingResource)) {
            try {
              value = ((ProcessingResource)source).getParameterValue(varname);
            } catch(Exception ex) {
              // do nothing, leave the value null
            }
          } else if(type.equals("doc") && (source instanceof Document)) {
            value = ((FeatureBearer)source).getFeatures().get(varname);
          } else if(type.equals("controller") && (source instanceof Controller)) {
            value = ((FeatureBearer)source).getFeatures().get(varname);
          } else if(type.equals("corpus") && (source instanceof Corpus)) {
            value = ((FeatureBearer)source).getFeatures().get(varname);