...
| Code Block | ||
|---|---|---|
| ||
public class MutableHolder {
private Hashtable<IntegerHashtable<Integer, String>String> value; // not final
public Object getValue() { return value; }
public void setValue(Hashtable<IntegerHashtable<Integer, String>String> ht) {
value = (Hashtable<IntegerHashtable<Integer, String>String>)ht;
}
}
|
This example also violates OBJ37-J. Defensively copy private mutable class members before returning their references.
...
| Code Block | ||
|---|---|---|
| ||
public class ImmutableHolder {
private final Hashtable<IntegerHashtable<Integer, String>String> value;
// create defensive copy of inputs
public ImmutableHolder(Hashtable<IntegerHashtable<Integer, String>String> ht) { value = (Hashtable<IntegerHashtable<Integer, String>String>)ht.clone(); }
// create defensive copy while returning
public Object getValue() { return value.clone(); }
}
|
...
| Wiki Markup |
|---|
\[[API 06|AA. Java References#API 06]\] Class {{System}}
\[[Commes 07|AA. Java References#Commes 07]\] Garbage Collection Concepts and Programming Tips
\[[Goetz 04|AA. Java References#Goetz 04]\]
\[[Lo 05|AA. Java References#Lo 05]\]
\[[Bloch 08|AA. Java References#Bloch 08]\] Item 6: ""Eliminate obsolete object references""
\[[MITRE 09|AA. Java References#MITRE 09]\] [CWE ID 405|http://cwe.mitre.org/data/definitions/405.html] ""Asymmetric Resource Consumption (Amplification)"" |
...
OBJ04-J. Encapsulate the absence of an object by using a Null Object 08. Object Orientation (OBJ) OBJ30-J. Do not ignore return values of methods that operate on immutable objects