Arrays & Strings
11.What is the output of the following code?
public class Main {
public static void main(String[] args) {
String str = " Java ";
System.out.println(str.trim());
}
}
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A. Java
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B. Java
-
C. Java
-
D. Java
Java
Java
12. What does the StringBuilder class provide in Java?
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A. Immutable string handling
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B. Fast and efficient string manipulation
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C. Better security than String
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D. Only works with arrays
Fast and efficient string manipulation
Fast and efficient string manipulation
13.What is the difference between String and StringBuilder?
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A. String is mutable, StringBuilder is immutable
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B. String is immutable, StringBuilder is mutable
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C. Both are immutable
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D. Both are mutable
String is immutable, StringBuilder is mutable
String is immutable, StringBuilder is mutable
14.What will be the output of the following code?
public class Main {
public static void main(String[] args) {
StringBuilder sb = new StringBuilder("Java");
sb.append(" Programming");
System.out.println(sb);
}
}
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A. JavaProgramming
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B. Java Programming
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C. Compilation error
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D. Java + Programming
Java Programming
Java Programming
15.What happens when you concatenate strings using + operator in Java?
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A. A new string is created each time
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B. The original string is modified
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C. Performance improves
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D. Compilation error
A new string is created each time
A new string is created each time