The program violates the Enterprise JavaBeans (EJB) specification by using AWT/Swing.
Extended Description
The Enterprise JavaBeans specification requires that every bean provider follow a set of programming guidelines designed to ensure that the bean will be portable and behave consistently in any EJB container. In this case, the program violates the following EJB guideline: "An enterprise bean must not use the AWT functionality to attempt to output information to a display, or to input information from a keyboard." The specification justifies this requirement in the following way: "Most servers do not allow direct interaction between an application program and a keyboard/display attached to the server system."
Relationships
The table(s) below shows the weaknesses and high level categories that are related to this weakness. These relationships are defined as ChildOf, ParentOf, MemberOf and give insight to similar items that may exist at higher and lower levels of abstraction. In addition, relationships such as PeerOf and CanAlsoBe are defined to show similar weaknesses that the user may want to explore.
Relevant to the view "Research Concepts" (CWE-1000)
Nature
Type
ID
Name
ChildOf
Base - a weakness
that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.
The different Modes of Introduction provide information about how and when this weakness may be introduced. The Phase identifies a point in the life cycle at which introduction may occur, while the Note provides a typical scenario related to introduction during the given phase.
Phase
Note
Architecture and Design
Implementation
Applicable Platforms
The listings below show possible areas for which the given weakness could appear. These may be for specific named Languages, Operating Systems, Architectures, Paradigms, Technologies, or a class of such platforms. The platform is listed along with how frequently the given weakness appears for that instance.
Languages
Java (Undetermined Prevalence)
Common Consequences
The table below specifies different individual consequences associated with the weakness. The Scope identifies the application security area that is violated, while the Impact describes the negative technical impact that arises if an adversary succeeds in exploiting this weakness. The Likelihood provides information about how likely the specific consequence is expected to be seen relative to the other consequences in the list. For example, there may be high likelihood that a weakness will be exploited to achieve a certain impact, but a low likelihood that it will be exploited to achieve a different impact.
Scope
Impact
Likelihood
Other
Technical Impact: Quality Degradation
Demonstrative Examples
Example 1
The following Java example is a simple converter class for converting US dollars to Yen. This converter class demonstrates the improper practice of using a stateless session Enterprise JavaBean that implements an AWT Component and AWT keyboard event listener to retrieve keyboard input from the user for the amount of the US dollars to convert to Yen.
(bad code)
Example Language: Java
@Stateless public class ConverterSessionBean extends Component implements KeyListener, ConverterSessionRemote {
/* member variables for receiving keyboard input using AWT API */
... private StringBuffer enteredText = new StringBuffer();
/* conversion rate on US dollars to Yen */
private BigDecimal yenRate = new BigDecimal("115.3100");
public ConverterSessionBean() {
super(); /* method calls for setting up AWT Component for receiving keyboard input */
... addKeyListener(this);
}
public BigDecimal dollarToYen(BigDecimal dollars) {
BigDecimal result = dollars.multiply(yenRate); return result.setScale(2, BigDecimal.ROUND_DOWN);
}
/* member functions for implementing AWT KeyListener interface */
public void keyTyped(KeyEvent event) {
...
}
public void keyPressed(KeyEvent e) { }
public void keyReleased(KeyEvent e) { }
/* member functions for receiving keyboard input and displaying output */
public void paint(Graphics g) {...}
...
}
This use of the AWT and Swing APIs within any kind of Enterprise JavaBean not only violates the restriction of the EJB specification against using AWT or Swing within an EJB but also violates the intended use of Enterprise JavaBeans to separate business logic from presentation logic.
The Stateless Session Enterprise JavaBean should contain only business logic. Presentation logic should be provided by some other mechanism such as Servlets or Java Server Pages (JSP) as in the following Java/JSP example.
(good code)
Example Language: Java
@Stateless public class ConverterSessionBean implements ConverterSessionRemoteInterface {
/* conversion rate on US dollars to Yen */ private BigDecimal yenRate = new BigDecimal("115.3100");
public ConverterSessionBean() { }
/* remote method to convert US dollars to Yen */
public BigDecimal dollarToYen(BigDecimal dollars) {
BigDecimal result = dollars.multiply(yenRate); return result.setScale(2, BigDecimal.ROUND_DOWN);
This MemberOf Relationships table shows additional CWE Categories and Views that reference this weakness as a member. This information is often useful in understanding where a weakness fits within the context of external information sources.
Nature
Type
ID
Name
MemberOf
Category - a CWE entry that contains a set of other entries that share a common characteristic.