Which statements about Java code security are true？（） A、 The bytecode verifier loads all classes needed for the execution of a program.B、 Executing code is performed by the runtime interpreter.C、 At runtime the bytecodes are loaded， checked and run in an interpreter.D、 The class loader adds security by separating the namespaces for the classes of the local file system from those imported from network sources.
Which statements about Java code security are true？（）
- A、 The bytecode verifier loads all classes needed for the execution of a program.
- B、 Executing code is performed by the runtime interpreter.
- C、 At runtime the bytecodes are loaded， checked and run in an interpreter.
- D、 The class loader adds security by separating the namespaces for the classes of the local file system from those imported from network sources.
相关考题：
Given:What is the result when the programmer attempts to compile the code and run it with the command java Converter 12?() A. It is true that j==i.B. It is false that j==i.C. An exception is thrown at runtime.D. Compilation fails because of an error in line 13.
Given:Which exception or error will be thrown when a programmer attempts to run this code?() A.java.lang.StackOverflowErrorB.java.lang.IllegalStateExceptionC.java.lang.ExceptionInInitializerErrorD.java.lang.ArrayIndexOutOfBoundsException
Given:What can be a result?() A.Compilation fails.B.An exception is thrown at runtime.C.The code executes and prints StartedComplete.D.The code executes and prints StartedComplete0123.E.The code executes and prints Started0123Complete.
public class Threads3 implements Runnable { public void run（） { System.out.print（”running”）； } public static void main（String[] args） { Thread t = new Thread（new Threads3（））； t.run（）； t.run（）； t.start（）； } } What is the result？（） A、 Compilation fails.B、 An exception is thrown at runtime.C、 The code executes and prints “running”.D、 The code executes and prints “runningrunning”.E、 The code executes and prints “runningrunningrunning”.
public class Threads5 { public static void main （String[] args） { new Thread（new Runnable（） { public void run（） { System.out.print（”bar”）； } }）.start（）； } } What is the result？（） A、 Compilation fails.B、 An exception is thrown at runtime.C、 The code executes normally and prints “bar”.D、 The code executes normally， but nothing prints.
public class Alpha{ public static void main（ string[] args ）{ if （ args.length == 2 ） { if （ args.[0].equalsIgnoreCase（“-b”） ） System.out.println（ new Boolean（ args[1] ））； } } } And the code is invoked by using the command： java Alpha –b TRUE What is the result？（） A、 trueB、 nullC、 falseD、 Compilation fails.E、 The code runs with no output.F、 An exception is thrown at runtime.
//point X public class foo { public static void main （String[]args） throws Exception { java.io.printWriter out = new java.io.PrintWriter { new java.io.outputStreamWriter （System.out）， true； out.printIn（“Hello”）； } } } Which statement at PointX on line 1 allows this code to compile and run？（） A、 Import java.io.*；B、 Include java.io.*；C、 Import java.io.PrintWriter；D、 Include java.io.PrintWriter；E、 No statement is needed.
Which statements about inheritance are true？（） A、 In Java programming language only allows single inheritance.B、 In Java programming language allows a class to implement only one interface.C、 In Java programming language a class cannot extend a class and implement a interface together.D、 In Java programming language single inheritance makes code more reliable.
//point X public class foo （ public static void main （Stringargs） throws Exception { printWriter out = new PrintWriter （new ） java.io.outputStreamWriter （System.out）， true； out.printIn（“Hello”）； } ） Which statement at PointX on line 1 allows this code to compile and run？（）A、 Import java.io.PrintWriter；B、 Include java.io.PrintWriter；C、 Import java.io.OutputStreamWriter；D、 Include java.io.OutputStreamWriter；E、 No statement is needed.
import java.util.*； public class NameList { private List names = new ArrayList（）； public synchronized void add（String name） { names.add（name）； } public synchronized void printAll（） { for （int i = 0； i System.out.print（names.get（i） +“ “）； } } public static void main（String[] args） { final NameList sl = new NameList（）； for（int i=0；i2；i++） { new Thread（） { public void ruin（） { sl.add（”A”）； sl.add（”B”）； sl.add（”C”）； sl.printAll（）； } }.start（）； } } } Which two statements are true if this class is compiled and run？（） A、 An exception may be thrown at runtime.B、 The code may run with no output， without exiting.C、The code may rum with output “A B A B C C “， then exit.D、The code may ruin with output “A A A B C A B C C “， then exit.E、 The code may rum with output “A B C A B C A B C “， then exit.F、The code may ruin with output “A B C A A B C A B C “， then exit.
class Computation extends Thread { private int num； private boolean isComplete； private int result； public Computation（int num） { this.num = num； } public synchronized void run（） { result = num * 2； isComplete = true； notify（）； } public synchronized int getResult（） { while （!isComplete） { try { wait（）； } catch （InterruptedException e） { } } return result； } public static void main（String[] args） { Computation[] computations = new Computation [4]； for （int i = 0； i computations.length； i++） { computations[i] = new Computation（i）； computations[i] .start（）； } for （Computation c ： computations） System.out.print（c.getResult（） +“ “）； } } What is the result？（） A、 The code will deadlock.B、 The code may run with no output.C、 An exception is thrown at runtime.D、 The code may run with output “0 6”.E、 The code may run with output “2 0 6 4‟.F、 The code may ruin with output “0 2 4 6”.
11.rbo = new ReallyBigObject（）； 12.//more code here 13.rbo = null； 14./*insert code here*/ Which statement should be placed at line 14 to suggest that the virtual machine expend effort toward recycling the memory used by the objectrbo？（）A、System.gc（）；B、Runtime.gc（）；C、System.freeMemory（）；D、Runtime.getRuntime（）.growHeap（）；E、Runtime.getRuntime（）.freeMemory（）；
Which statement is true when you run the SQL Tuning Advisor with limited scope？（）A、Access path analysis is not performed for the SQL statements.B、SQL structure analysis is not performed for the SQL statements.C、SQL Profile recommendations are not generated for the SQL statements.D、The staleness and absence of the statistics are not checked for the objects in the query supplied to the SQL Tuning Advisor.
What two statements are true about Oracle Enterprise Manager’s Java Diagnostic tool， which makes the tool suitable for production server diagnostics ？（）A、 virtually zero overhead for application running in the JVM B、 no stalling of running JVM when taking a heap dump for memory analysis C、 no need of modification， changes， or instrumentation of the application since is uses Network Protocol Analysis （NPA technology）D、 provides Byte Code Instrumentation for Java
单选题public class Threads3 implements Runnable { public void run（） { System.out.print（”running”）； } public static void main（String[] args） { Thread t = new Thread（new Threads3（））； t.run（）； t.run（）； t.start（）； } } What is the result？（）A Compilation fails.B An exception is thrown at runtime.C The code executes and prints “running”.D The code executes and prints “runningrunning”.E The code executes and prints “runningrunningrunning”.
单选题Given： What is the result？（）A Compilation fails.B An exception is thrown at runtime.C The code executes normally and prints "sleep".D The code executes normally， but nothing is printed.
单选题You work as an application developer at Certkiller .com. Certkiller .com has asked you to create a multi-threaded application， which executes a critical database backup operation on an hourly basis. You define this operation with the following code： public void BackupDB （） { //Implementation code } You then create a Thread object for the purpose of invoking this method. You need to ensure that the thread is scheduled for execution before any other thread at runtime.What should you do？（）A AB BC CD D
单选题Click the Exhibit button. What is the result？（）A The code will deadlock.B The code may run with output "2 0 6 4".C The code may run with no output.D The code may run with output "0 6".E An exception is thrown at runtime.F The code may run with output "0 2 4 6".
单选题Given: What is the result？（）A Compilation fails.B An exception is thrown at runtime.C The code executes and prints "running".D The code executes and prints "runningrunning".E The code executes and prints "runningrunningrunning".
单选题11. rbo = new ReallyBigObject（）； 12. // more code here 13. rbo = null； 14. /* insert code here */ Which statement should be placed at line 14 to suggest that the virtual machine expend effort toward recycling the memory used by the object rbo？（）A System.gc（）；B Runtime.gc（）；C System.freeMemory（）；D Runtime.getRuntime（）.growHeap（）；E Runtime.getRuntime（）.freeMemory（）；
多选题Which statements about Java code security are true？（）AThe bytecode verifier loads all classes needed for the execution of a program.BExecuting code is performed by the runtime interpreter.CAt runtime the bytecodes are loaded， checked and run in an interpreter.DThe class loader adds security by separating the namespaces for the classes of the local file system from those imported from network sources.
单选题//point X public class foo （ public static void main （Stringargs） throws Exception { printWriter out = new PrintWriter （new ） java.io.outputStreamWriter （System.out）， true； out.printIn（“Hello”）； } ） Which statement at PointX on line 1 allows this code to compile and run？（）A Import java.io.PrintWriter；B Include java.io.PrintWriter；C Import java.io.OutputStreamWriter；D Include java.io.OutputStreamWriter；E No statement is needed.
单选题//point X public class foo { public static void main （Stringargs） throws Exception { java.io.printWriter out = new java.io.PrintWriter { new java.io.outputStreamWriter （System.out）， true； out.printIn（“Hello”）； } } } Which statement at PointX on line 1 allows this code to compile and run？（）A Import java.io.*；B Include java.io.*；C Import java.io.PrintWriter；D Include java.io.PrintWriter；E No statement is needed.
单选题public class Alpha{ public static void main（ string[] args ）{ if （ args.length == 2 ） { if （ args.[0].equalsIgnoreCase（“-b”） ） System.out.println（ new Boolean（ args[1] ））； } } } And the code is invoked by using the command： java Alpha –b TRUE What is the result？（）A trueB nullC falseD Compilation fails.E The code runs with no output.F An exception is thrown at runtime.
单选题Which statements， when inserted at the indicated position in the following code， will cause a runtime exception when attempting to run the program？（） class A {} class B extends A {} class C extends A {} public class Q3ae4 { public static void main（String args[]） { A x = new A（）； B y = new B（）； C z = new C（）； // insert statement here } }Ax = y；Bz = x；Cy = （B） x；Dz = （C） y；Ey = （A） y；
多选题Which statements about inheritance are true？（）AIn Java programming language only allows single inheritance.BIn Java programming language allows a class to implement only one interface.CIn Java programming language a class cannot extend a class and implement a interface together.DIn Java programming language single inheritance makes code more reliable.
单选题You are loading a new assembly into an application. You need to override the default evidence for the assembly. You require the common language runtime （CLR） to grant the assembly a permission set，as if the assembly were loaded from the local intranet zone. You need to build the evidence collection. Which code segment should you use？（）A AB BC CD D