多选题Which of the following statements about variables and their scopes are true？ （）AInstance variables are member variables of a class.BInstance variables are declared with the static keyword.CLocal variables defined inside a method are created when the me

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第2题：

Which three statements are true？（）

• A、 The default constructor initializes method variables.
• B、 The default constructor has the same access as its class.
• C、 The default constructor invoked the no-arg constructor of the superclass.
• D、 If a class lacks a no-arg constructor， the compiler always creates a default constructor. 
• E、 The compiler creates a default constructor only when there are no other constructors for the class.

第3题：

Which two statements are true regarding the creation of a default constructor？（） 

• A、 The default constructor initializes method variables.
• B、 The compiler always creates a default constructor for every class.
• C、 The default constructor invokes the no-parameter constructor of the superclass.
• D、 The default constructor initializes the instance variables declared in the class.
• E、 When a class has only constructors with parameters， the compiler does not create a default constructor.

第4题：

Given that Thing is a class， how many objects and reference variables are created by the following code？（）   Thing item， stuff；   item = new Thing（）；   Thing entity = new Thing（）；

• A、One object is created
• B、Two objects are created
• C、Three objects are created
• D、One reference variable is created
• E、Two reference variables are created
• F、Three reference variables are created.

第5题：

Which of the following statements about variables and scope are true？（） 

• A、 Local variables defined inside a method are destroyed when the method is exited.
• B、 Local variables are also called automatic variables.
• C、 Variables defined outside a method are created when the object is constructed.
• D、 A method parameter variable continues to exist for as long as the object is needed in which the method is defined.

第6题：

Which statement is true？（）

• A、 An anonymous inner class may be declared as final.
• B、 An anonymous inner class can be declared as private.
• C、 An anonymous inner class can implement multiple interfaces.
• D、 An anonymous inner class can access final variables in any enclosing scope.
• E、 Construction of an instance of a static inner class requires an instance of the enclosing outer class.

第7题：

Which of the following statements about variables and their scopes are true？ （）   

• A、 Instance variables are member variables of a class.
• B、 Instance variables are declared with the static keyword.
• C、 Local variables defined inside a method are created when the method is executed.
• D、 Local variables must be initialized before they are used.

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第13题：

Which statements concerning the correlation between the inner and outer instances of non-static inner classes are true？（）  

• A、Member variables of the outer instance are always accessible to inner instances， regardless of their      accessibility modifiers.
• B、Member variables of the outer instance can never be referred to using only the variable name within     the inner instance.
• C、More than one inner instance can be associated with the same outer instance.
• D、All variables from the outer instance that should be accessible in the inner instance must be declared     final.
• E、A class that is declared final cannot have any inner classes.

第14题：

Which two statements are true regarding the creation of a default constructor？（）   

• A、 The default constructor initializes method variables.
• B、 The default constructor invokes the no-parameter constructor of the superclass.
• C、 The default constructor initializes the instance variables declared in the class.
• D、 If a class lacks a no-parameter constructor，， but has other constructors， the compiler creates a default constructor.
• E、 The compiler creates a default constructor only when there are no other constructors for the class.

第15题：

Which statements concerning the value of a member variable are true， when no explicit assignments have been made？（）  

• A、The value of an int is undetermined.
• B、The value of all numeric types is zero.
• C、The compiler may issue an error if the variable is used before it is initialized.
• D、The value of a String variable is "" （empty string）.
• E、The value of all object variables is null.

第16题：

状态变量 (state variables)

第17题：

Which two are true about has-a and is-a relationships？（）

• A、 Inheritance represents an is-a relationship.
• B、 Inheritance represents a has-a relationship.
• C、 Interfaces must be used when creating a has-a relationship.
• D、 Instance variables can be used when creating a has-a relationship.

第18题：

You execute the following commands to audit database activities: SQL > ALTER SYSTEM SET AUDIT_TRIAL=DB, EXTENDED SCOPE=SPFILE; SQL > AUDIT SELECT TABLE, INSERT TABLE, DELETE TABLE BY JOHN By SESSION WHENEVER SUCCESSFUL; Which statement is true about the audit record that generated when auditing after instance restarts?（）

• A、One audit record is created for every successful execution of a SELECT, INSERT OR DELETE command on a table, and contains the SQL text for the SQL Statements.
• B、One audit record is created for every successful execution of a SELECT, INSERT OR DELETE command, and contains the execution plan for the SQL statements.
• C、One audit record is created for the whole session if john successfully executes a SELECT, INSERT, or DELETE command, and contains the execution plan for the SQL statements.
• D、One audit record is created for the whole session if JOHN successfully executes a select command, and contains the SQL text and bind variables used.
• E、One audit record is created for the whole session if john successfully executes a SELECT, INSERT,or DELETE command on a table, and contains the execution plan, SQL text, and bind variables used.

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