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Given a class whose instances, when found in a collection of objects, are sorted by using the compareTo()method, which two statements are true?（）
A . The class implements java.lang.Comparable.
B . The class implements java.util.Comparator.
C . The interface used to implement sorting allows this class to define only one sort sequence.
D . The interface used to implement sorting allows this class to define many different sort sequences.
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Given： 1.package test； 2. 3.class Target { 4.public String name = "hello"；5.} What can directly access and change the value of the variable name？（）
A . any class
B . only the Target class
C . any class in the test package
D . any class that extends Target
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Click the Exhibit button.
https://assets.asklib.com/images/image2/2018080113413786465.png
Given this code from Class B：
25.A a1 = new A（）；
26.A a2 = new A（）；
27.A a3 = new A（）；
28.System.out.println（A.getInstanceCount（））；
What is the result？（）
A . Compilation of class A fails.
B . Line 28 prints the value 3 to System.out.
C . Line 28 prints the value 1 to System.out.
D . A runtime error occurs when line 25 executes.
E . Compilation fails because of an error on line 28.
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Given a class Repetition：
https://assets.asklib.com/images/image2/2018080111013543546.png
Which code should be inserted at line 1 of Demo.java to compile and run Demo to print "pizzapizza"？（）
A . import utils.*；
B . static import utils.*；
C . import utils.Repetition.*；
D . static import utils.Repetition.*；
E . import utils.Repetition.twice（）；
F . import static utils.Repetition.twice；
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Given the following class， which statements can be inserted at position 1 without causing the code to fail compilation？（） public class Q6db8 { int a； int b = 0； static int c； public void m（） { int d； int e = 0； // Position 1 } }
A . a++；
B . b++；
C . c++；
D . d++；
E . e++；
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Given the following code： public class Person{ int arr[] = new int[10]； public static void main（String a[]） { System.out.println（arr[1]）； } } Which statement is correct？（）
A . When compilation some error will occur.
B . It is correct when compilation but will cause error when running.
C . The output is zero.
D . The output is null.
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Click the Exhibit button.
Given this code from Class B：
25. A a1 = new A（）；
26. A a2 = new A（）；
27. A a3 = new A（）；
28. System.out.println（A.getInstanceCount（））；
What is the result？（）
https://assets.asklib.com/images/image2/2018080115393687033.jpg
A . Compilation of class A fails.
B . Line 28 prints the value 3 to System.out.
C . Line 28 prints the value 1 to System.out.
D . Compilation fails because of an error on line 28.
E . A runtime error occurs when line 25 executes.
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Given： 1. public class Method Over { 2. public void set Var （int a， int b， float c） { 3. } 4. } Which two overload the set Var method（）？
A . private void set Var（int a， float c， int b） {}
B . protected void set Var（int a， int b， float c） {}
C . public int set Var（int a， float c， int b） {return a：}
D . public int set Var（int a， int b， float c） {return a：}
E . protected float set Var（int a， int b， float c） {return c：}
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Given the following code： public class Person{ static int arr[] = new int[10]； public static void main（String a[]） { System.out.println（arr[1]；） } } Which statement is correct？（）
A . When compilation some error will occur.
B . It is correct when compilation but will cause error when running.
C . The output is zero.
D . The output is null.
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Given a pre-generics implementation of a method：
https://assets.asklib.com/images/image2/2018080110591931008.png
What three changes allow the class to be used with generics and avoid an unchecked warning？（）
A . Remove line 14.
B . Replace line 14 with "int i = iter.next（）；".
C . Replace line 13 with "for （int i ： intList） {".
D . Replace line 13 with "for （Iterator iter ： intList） {".
E . Replace the method declaration with "sum（List
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Click the Exhibit button. Given:Which statement is true if a TestException is thrown on line 3 of class B? （）https://assets.asklib.com/images/image2/2018080209451430879.jpg
A . Line 33 must be called within a try block.
B . The exception thrown by method1 in class A is not required to be caught.
C . The method declared on line 31 must be declared to throw a RuntimeException.
D . On line 5 of class A, the call to method2 of class B does not need to be placed in a try/catch block.
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1.public class Test{ 2.int x=12； 3.public void method（intx）{ 4.x+=x； 5.System.out.println（x）； 6.} 7.} Given： 34.Test t=new Test（）； 35.t.method（5）； What is the output from line 5 of the Test class？（）
A . 5
B . 10
C . 12
D . 17
E . 24
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1. public class A { 2. public String doit（int x， int y） { 3. return “a”； 4. } 5. 6. public String doit（int... vals） { 7. return “b”； 8. } 9. } Given： 25. A a=new A（）； 26. System.out.println（a.doit（4， 5））； What is the result？（）
A . Line 26 prints “a” to System.out.
B . Line 26 prints „b” to System.out.
C . An exception is thrown at line 26 at runtime.
D . Compilation of class A will fail due to an error in line 6.
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Given a class whose instances， when found in a collection of objects， are sorted by using the compareTo（） method， which two statements are true？（）
A . The class implements java.lang.Comparable.
B . The class implements java.util.Comparator.
C . The interface used to implement sorting allows this class to define only one sort sequence.
D . The interface used to implement sorting allows this class to define many different sort sequences.
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Given 1. public class Foo { 2. public static void main （String [] args） } 3. try { return；} 4. finally { Syste.out.printIn （“Finally”）；} 5. } 6. } What is the result()？
A . The program runs and prints nothing.
B . The program runs and prints “Finally”.
C . The code comiles. But an exception is thrown at runtime.
D . The code will not compile because the catch block is missing.
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Given this method in a class： public String toString（） { StringBuffer buffer = new StringBuffer（）； buffer.append（‟<‟）； buffer.append（this.name）； buffer.append（‟>‟）； return buffer.toString（）； } Which is true？（）
A . This code is NOT thread-safe.
B . The programmer can replace StringBuffer with StringBuilder with no other changes.
C . This code will perform well and converting the code to use StringBuilder will not enhance the performance.
D . This code will perform poorly. For better performance， the code should be rewritten： return “<“+ this.name + “>”；
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Given： 1. public class ConstOver { 2. public constOver（int x， int y， int z） { 3. } 4. } Which two overload the ConstOver Constructor？（）
A . ConstOver（） {}
B . protected int ConstOver（）{}
C . private ConstOver（int z， int y， byte x ） {}
D . public Object ConstOver（Int x， int y， int z） {}
E . pubic void ConstOver （byte x， byte y， byte z） {}
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Given a class whose instances， when found in a collection of objects， are sorted by using the compare To method， which two statements are true？（）
A . The class implements java.lang.Comparable.
B . The class implements java.util.Comparator.
C . The interface used to implement sorting allows this class to define only one sort sequence.
D . The interface used to implement sorting allows this class to define many different sort sequences.
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Given a class Repetition:
https://assets.asklib.com/images/image2/2018080116125392704.jpg
Which code should be inserted at line 1 of Demo.java to compile and run Demo to print "pizzapizza"?（）
A . import utils.*;
B . static import utils.*;
C . import utils.Repetition.*;
D . static import utils.Repetition.*;
E . import utils.Repetition.twice();
F . import static utils.Repetition.twice;
G . static import utils.Repetition.twice
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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.
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For this part, you are allowed 30 minutes to write a short essay entitled Class Attendance. You should write at least 150 words according to the outline given below in Chinese:
1．有人认为大学生必须去上课
2．有人认为不应该强迫大学生上课
3．我认为…
Class Attendance
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In your first days at the school you’ll be given a test to help the teachers to ________ you to a class at your level.
A) locate
B) assign
C) deliver
D) place
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Click the Exhibit button. Given:Which two statements are true if a NullPointerException is thrown on line 3 of class C？ （）
<img src='https://img2.soutiyun.com/ask/uploadfile/2019-03-27/900591de4611848eaa661230b23f7c01.jpg' />
<img src='https://img2.soutiyun.com/ask/uploadfile/2019-03-27/096a8f1a86972212e5c4d4c53f88ec71.jpg' />
A.The application will crash.
B.The code on line 29 will be executed.
C.The code on line 5 of class A will execute.
D.The code on line 5 of class B will execute.
E.The exception will be propagated back to line 27.
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Given the uncompleted code of a class:class Person { String name, department; int age; public Person（String n）{ name = n; } public Person（String n, int a）{ name = n; age = a; } public Person（String n,
A．Person（n,a）
B．this（Person（n,a））
C．this（n,a）
D．this（name,age）
