while (result                                                                         
        && !isUsedVariableDeclarationFound                                            
        && currentSiblingAst != null) {                                               
    switch (currentSiblingAst.getType()) {                                            
        case TokenTypes.EXPR:                                                         
            final DetailAST methodCallAst = currentSiblingAst.getFirstChild();        
                                                                                      
            if (methodCallAst.getType() == TokenTypes.METHOD_CALL) {                  
                final String instanceName =                                           
                    getInstanceName(methodCallAst);                                   
                // method is called without instance                                  
                if (instanceName.isEmpty()) {                                         
                    result = false;                                                   
                }                                                                     
                // differs from previous instance                                     
                else if (!instanceName.equals(initInstanceName)) {                    
                    if (initInstanceName.isEmpty()) {                                 
                        initInstanceName = instanceName;                              
                    }                                                                 
                    else {                                                            
                        result = false;                                               
                    }                                                                 
                }                                                                     
            }                                                                         
            else {                                                                    
                // is not method call                                                 
                result = false;                                                       
            }                                                                         
            break;                                                                    
                                                                                      
        case TokenTypes.VARIABLE_DEF:                                                 
            final String currentVariableName = currentSiblingAst                      
                .findFirstToken(TokenTypes.IDENT).getText();                          
            isUsedVariableDeclarationFound = variableName.equals(currentVariableName);
            break;                                                                    
                                                                                      
        default:                                                                      
            result = currentSiblingAst.getType() == TokenTypes.SEMI;                  
    }                                                                                 
                                                                                      
    currentSiblingAst = currentSiblingAst.getPreviousSibling();                       
}