Program: 934
Project: 934
Buggy source:
/** 
 * @param params a set of string parameter
 * @param callingClient the responsible client (passed as last parameter)
 * @return the return value of the method call or an empty string, never <code>null</code>.
 * @throws IllegalArgumentException if the method call was not successful 
 * @throws Exception if something went seriously wrong
 */
public String execute(List<String> params,EntityRef callingClient) throws Exception {
  Object[] processedParams=new Object[method.getParameterTypes().length];
  if (isClientEntityRequired()) {
    if (params.size() + 1 != method.getParameterTypes().length) {
      throw new IllegalArgumentException("String_Node_Str" + (method.getParameterTypes().length - 1));
    }
    processedParams[processedParams.length - 1]=callingClient;
  }
 else   if (params.size() != method.getParameterTypes().length) {
    throw new IllegalArgumentException("String_Node_Str" + (method.getParameterTypes().length));
  }
  for (int i=0; i < params.size(); ++i) {
    try {
      Class<?> type=method.getParameterTypes()[i];
      if (type == Float.TYPE) {
        processedParams[i]=Float.parseFloat(params.get(i));
      }
 else       if (type == Integer.TYPE) {
        processedParams[i]=Integer.parseInt(params.get(i));
      }
 else       if (type == String.class) {
        String value=params.get(i);
        if (value.startsWith("String_Node_Str") && value.endsWith("String_Node_Str")) {
          value=value.substring(1,value.length() - 1);
        }
        processedParams[i]=value;
      }
    }
 catch (    NumberFormatException e) {
      throw new NumberFormatException("String_Node_Str" + params.get(i) + "String_Node_Str");
    }
  }
  try {
    Object result=method.invoke(provider,processedParams);
    return (result != null) ? result.toString() : "String_Node_Str";
  }
 catch (  InvocationTargetException ite) {
    Throwable e=ite.getTargetException();
    throw new IllegalArgumentException(e.getLocalizedMessage(),e);
  }
}

Fixed version (ground truth):
/** 
 * @param params a set of string parameter
 * @param callingClient the responsible client (passed as last parameter)
 * @return the return value of the method call or an empty string, never <code>null</code>.
 * @throws IllegalArgumentException if the method call was not successful 
 * @throws Exception if something went seriously wrong
 */
public String execute(List<String> params,EntityRef callingClient) throws Exception {
  Object[] processedParams=new Object[method.getParameterTypes().length];
  if (isClientEntityRequired()) {
    if (params.size() + 1 != method.getParameterTypes().length) {
      throw new IllegalArgumentException("String_Node_Str" + (method.getParameterTypes().length - 1));
    }
    processedParams[processedParams.length - 1]=callingClient;
  }
 else   if (params.size() != method.getParameterTypes().length) {
    throw new IllegalArgumentException("String_Node_Str" + (method.getParameterTypes().length));
  }
  for (int i=0; i < params.size(); ++i) {
    try {
      Class<?> type=method.getParameterTypes()[i];
      if (type == Float.TYPE) {
        processedParams[i]=Float.parseFloat(params.get(i));
      }
 else       if (type == Integer.TYPE) {
        processedParams[i]=Integer.parseInt(params.get(i));
      }
 else       if (type == String.class) {
        String value=params.get(i);
        processedParams[i]=value;
      }
    }
 catch (    NumberFormatException e) {
      throw new NumberFormatException("String_Node_Str" + params.get(i) + "String_Node_Str");
    }
  }
  try {
    Object result=method.invoke(provider,processedParams);
    return (result != null) ? result.toString() : "String_Node_Str";
  }
 catch (  InvocationTargetException ite) {
    Throwable e=ite.getTargetException();
    throw new IllegalArgumentException(e.getLocalizedMessage(),e);
  }
}