Mastering Java String Handling

What is the result of concatenating 'Hello' and 'World' in Java?

• WorldHello

• Hello World

• HelloWorld

• HelloWorld!

Which method is used to compare two strings for equality in Java?

• stringCompare()

• isEqual()

• compareTo()

• equals()

How do you format a string to include a variable in Java?

• StringBuilder sb = new StringBuilder(); sb.append("Hello, ").append(variable);

• String.replace("Hello, %s!", "%s", variable);

• Use String.format("Hello, %s!", variable) or concatenation with +.

• Use printf("Hello, %s!", variable);

What method would you use to find the index of a character in a string?

• Use the 'search' method.

• Use the 'find' method.

• Use the 'indexOf' method.

• Use the 'locate' method.

Explain the concept of string immutability in Java.

• String immutability allows changing characters in a string.

• Strings in Java can be modified after creation.

• String immutability in Java means that once a string is created, it cannot be changed.

• Strings in Java are mutable and can be resized.

What is the output of 'Java'.concat(' Programming')?

• Java Programming

• Java: Programming

• Java Programming Language

• Java and Programming

How can you compare two strings lexicographically in Java?

• Use str1.compare(str2) to compare two strings lexicographically.

• Use str1.compareTo(str2) to compare two strings lexicographically.

• Use str1.equalsIgnoreCase(str2) to compare two strings lexicographically.

• Use str1.equals(str2) to compare two strings lexicographically.

What is the purpose of the String.format() method?

• To concatenate two strings together.

• To convert a string to uppercase.

• To split a string into an array of characters.

• To format strings by replacing placeholders with specified values.

Which method checks if a string contains a specific sequence of characters?

• The 'substring()' method (JavaScript)

• The 'find()' method (Python)

• The 'in' operator (Python) or 'includes()' method (JavaScript)

• The 'search()' function (Java)

What happens when you try to modify a string in Java?

• Modifying a string changes the original string directly.

• Modifying a string creates a new string; the original remains unchanged.

• You can modify a string by using the StringBuilder class.

• Strings in Java are mutable and can be altered in place.