logback-android/src/main/java/ch/qos/logback/core/joran/action/ConversionRuleAction.java
@SuppressWarnings("unchecked")
  public void begin(InterpretationContext ec, String localName, Attributes attributes) {
    // Let us forget about previous errors (in this object)
    inError = false;

    String errorMsg;
    String conversionWord =
      attributes.getValue(ActionConst.CONVERSION_WORD_ATTRIBUTE);
    String converterClass =
      attributes.getValue(ActionConst.CONVERTER_CLASS_ATTRIBUTE);

    if (OptionHelper.isEmpty(conversionWord)) {
      inError = true;
      errorMsg = "No 'conversionWord' attribute in <conversionRule>";
      addError(errorMsg);

      return;
    }

    if (OptionHelper.isEmpty(converterClass)) {
      inError = true;
      errorMsg = "No 'converterClass' attribute in <conversionRule>";
      ec.addError(errorMsg);

      return;
    }

    try {
      Map<String, String> ruleRegistry = (Map<String, String>) context.getObject(CoreConstants.PATTERN_RULE_REGISTRY);
      if(ruleRegistry == null) {
        ruleRegistry = new HashMap<String, String>();
        context.putObject(CoreConstants.PATTERN_RULE_REGISTRY, ruleRegistry);
      }
      // put the new rule into the rule registry
      addInfo("registering conversion word "+conversionWord+" with class ["+converterClass+"]");
      ruleRegistry.put(conversionWord, converterClass);
    } catch (Exception oops) {
      inError = true;
      errorMsg = "Could not add conversion rule to PatternLayout.";
      addError(errorMsg);
    }
  }
@SuppressWarnings("unchecked")
  public void begin(InterpretationContext ec, String localName, Attributes attributes) {
    // Let us forget about previous errors (in this object)
    inError = false;

    String errorMsg;
    String conversionWord =
      attributes.getValue(ActionConst.CONVERSION_WORD_ATTRIBUTE);
    String converterClass =
      attributes.getValue(ActionConst.CONVERTER_CLASS_ATTRIBUTE);

    if (OptionHelper.isEmpty(conversionWord)) {
      inError = true;
      errorMsg = "No 'conversionWord' attribute in <conversionRule>";
      addError(errorMsg);

      return;
    }

    if (OptionHelper.isEmpty(converterClass)) {
      inError = true;
      errorMsg = "No 'converterClass' attribute in <conversionRule>";
      ec.addError(errorMsg);

      return;
    }

    try {
      Map<String, String> ruleRegistry = (Map<String, String>) context.getObject(CoreConstants.PATTERN_RULE_REGISTRY);
      if(ruleRegistry == null) {
        ruleRegistry = new HashMap<String, String>();
        context.putObject(CoreConstants.PATTERN_RULE_REGISTRY, ruleRegistry);
      }
      // put the new rule into the rule registry
      addInfo("registering conversion word "+conversionWord+" with class ["+converterClass+"]");
      ruleRegistry.put(conversionWord, converterClass);
    } catch (Exception oops) {
      inError = true;
      errorMsg = "Could not add conversion rule to PatternLayout.";
      addError(errorMsg);
    }
  }
Instantiates an layout of the given class and sets its name.