if (instance == null) { instance = new LogRecordList(); } return instance;
if (myInstance == null) { myInstance = new NullWorkerStatusController(); } return myInstance;
Clone fragments detected by clone detection tool
File path: /columba-1.4-src/plugins/org.columba.core.LogDisplay/src/org/columba/core/gui/logdisplay/LogRecordList.java File path: /columba-1.4-src/core/src/main/java/org/columba/core/command/NullWorkerStatusController.java
Method name: LogRecordList getInstance() Method name: NullWorkerStatusController getInstance()
Number of AST nodes: 3 Number of AST nodes: 3
1
if (instance == null) {
1
if (myInstance == null) {
2
            instance = new LogRecordList();
2
	    myInstance = new 
3
        }
4
        
3
NullWorkerStatusController();
4
	}
5
return instance;
5
	return myInstance;
Summary
Number of common nesting structure subtrees1
Number of refactorable cases0
Number of non-refactorable cases1
Time elapsed for finding largest common nesting structure subtrees (ms)0.1
Clones locationClones are in different classes
Number of node comparisons5
  1. {Non-refactorable}
    Mapping Summary
    Number of mapped statements1
    Number of unmapped statements in the first code fragment2
    Number of unmapped statements in the second code fragment2
    Time elapsed for statement mapping (ms)0.6
    Clone typeType 2
    Mapped Statements
    ID Statement ID Statement
    1
    if (instance == null)
    1
    if (instance == null)
    1
    if (myInstance == null)
    Differences
    Expression1Expression2Difference
    instancemyInstanceVARIABLE_NAME_MISMATCH
    org.columba.core.gui.logdisplay.LogRecordListorg.columba.core.command.NullWorkerStatusControllerVARIABLE_TYPE_MISMATCH
    Preondition Violations
    Type org.columba.core.gui.logdisplay.LogRecordList of variable instance does not match with type org.columba.core.command.NullWorkerStatusController of variable myInstance
    • Make classes org.columba.core.gui.logdisplay.LogRecordList and org.columba.core.command.NullWorkerStatusController extend a common superclass
    1
    if (myInstance == null)
                                                                                                  
    2
    myInstance = new NullWorkerStatusController();
    Preondition Violations
    Unmatched statement myInstance=new NullWorkerStatusController(); cannot be moved before the extracted code, because it has control dependencies from statements that will be extracted
    2
    myInstance = new NullWorkerStatusController();
    2
    instance = new LogRecordList();
    2
    instance = new LogRecordList();
    Preondition Violations
    Unmatched statement instance=new LogRecordList(); cannot be moved before the extracted code, because it has control dependencies from statements that will be extracted
                                                                    
                                              
    3
    return myInstance;
    Preondition Violations
    Unmatched return myInstance;
    3
    return myInstance;
    3
    return instance;
    3
    return instance;
    Preondition Violations
    Unmatched return instance;
                                          
    Precondition Violations (6)
    Row Violation
    1Type org.columba.core.gui.logdisplay.LogRecordList of variable instance does not match with type org.columba.core.command.NullWorkerStatusController of variable myInstance
    2Unmatched statement myInstance=new NullWorkerStatusController(); cannot be moved before the extracted code, because it has control dependencies from statements that will be extracted
    3Unmatched statement instance=new LogRecordList(); cannot be moved before the extracted code, because it has control dependencies from statements that will be extracted
    4Unmatched return myInstance;
    5Unmatched return instance;
    6The refactoring of the clones is infeasible, because the number of macthed statements is equal to zero