Test on JAVA test P7

Question 1. Which method is used to search a string in another string in Java's String class?
- astIndexOf ()
- substring ()
- toString ()
- No answer right
Question 2. In Java, what data type is an object's address or an array created in memory?
- Primitive type
- Reference type
- Format
- There is no right answer
Question 3. What is the function of the while loop?
- Check the result of the boolean expression
- Avoid conflict between inside and outside the switch
- Repeat the command block to see if the condition is correct
- No answer right
Question 4. Java provides a number of commands that change control flow based on conditions. Which command stops the operation of the inner lap and starts the next statement immediately after the block?
- break
- tiếp tục
- thay đổi
- jump
Question 5. Result = condition command? What does value1: value2 mean?
- If condition is true then result = value2, if condition is false, result = value1
- If condition is true then result = value1, if condition is false then result = value2
- There is no such command
- If condition is true, the result will invert the value of value1 and value2
Question 6. Which command stops the current loop and starts the next loop?
- tiếp tục
- break
- cease
- end
Question 7. Which of the following statements is correct?
- int [] a;
- int a [];
- int a [] = new int [10];
- All 3 statements are correct

Question 8. How many changes of the array object reference and variable exist after executing the block?

 String [] students = new String [10]; 

 String studentName = 'Peter Parker'; 

 students [0] = studentName; 

 studentName = null;

Sentence 9. Assumption Rectangle class is defined and not false. When running, the program reported an error because:
```
 public class SomeWrong { 

 public static void main (String [] args) { 

 MyRect Rectangle; 

 myRect.width = 40; 

 myRect.height = 50; 

 System.out.println ('Standard delivery:' + myRect.area ()); 

 } 

 } 
```
- MyRect has not been initialized yet
- There is no processing method
- There is no static keyword
- The program is not wrong
Question 10. To inverse the value of a boolean variable, which operator do we use?
- !
- >>
- <<
- >>>

A set of multiple-choice questions about Java gives you useful knowledge for work and study. The set of questions below includes 10 sentences for you to experience.