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Question-1. What is Groovy?
Answer-1: Groovy is an object-oriented scripting language for the Java platform that enhances productivity.
Question-2. How is Groovy related to Java?
Answer-2: Groovy runs on the JVM and is fully compatible with Java libraries and frameworks.
Question-3. What are the key features of Groovy?
Answer-3: Concise syntax, dynamic typing, closures, builders, and seamless Java integration.
Question-4. What is a Groovy script?
Answer-4: A Groovy script is a Groovy program written without a class declaration.
Question-5. What file extension is used for Groovy scripts?
Answer-5: .groovy
Question-6. How do you declare a variable in Groovy?
Answer-6: Variables are declared using def, or directly with a type like String. Example: def x = 10.
Question-7. What are closures in Groovy?
Answer-7: Closures are anonymous blocks of code that can accept arguments, return values, and be assigned to variables.
Question-8. How do you define a closure in Groovy?
Answer-8: Use {}. Example: { println "Hello, World!" }.
Question-9. What is the default access modifier in Groovy?
Answer-9: The default access modifier in Groovy is public.
Question-10. How do you write comments in Groovy?
Answer-10: Use // for single-line comments and /* */ for multi-line comments.
Question-11. What are GStrings in Groovy?
Answer-11: GStrings are strings that support interpolation using ${} syntax.
Question-12. How do you concatenate strings in Groovy?
Answer-12: Use + or GString interpolation. Example: "Hello, ${name}".
Question-13. What are Groovy ranges?
Answer-13: Groovy ranges define a sequence of values using .. or ..<.
Question-14. How do you define a range in Groovy?
Answer-14: Example: 1..10 creates a range from 1 to 10.
Question-15. How does Groovy handle null values?
Answer-15: Groovy has safe navigation (?.) and Elvis (?:) operators to handle nulls.
Question-16. What is the Elvis operator in Groovy?
Answer-16: The ?: operator returns the left-hand operand if it's non-null; otherwise, it returns the right-hand operand.
Question-17. How do you iterate over a list in Groovy?
Answer-17: Use each or traditional for. Example: list.each { println it }.
Question-18. What is a Groovy map?
Answer-18: A map is a collection of key-value pairs. Example: [key1: value1, key2: value2].
Question-19. How do you create a list in Groovy?
Answer-19: Use square brackets. Example: [1, 2, 3].
Question-20. How do you create a map in Groovy?
Answer-20: Use square brackets with colons. Example: [name: "John", age: 30].
Question-21. What are Groovy builders?
Answer-21: Builders are utility classes for creating XML, JSON, or UI elements programmatically.
Question-22. How do you define a method in Groovy?
Answer-22: Use def or specific types. Example: def add(a, b) { return a + b }.
Question-23. What is the @Grab annotation in Groovy?
Answer-23: @Grab allows importing dependencies at runtime using Grape.
Question-24. How do you handle exceptions in Groovy?
Answer-24: Use try-catch-finally blocks. Example: try { ... } catch(Exception e) { ... }.
Question-25. What are categories in Groovy?
Answer-25: Categories are used to add methods dynamically to classes.
Question-26. How do you define a category in Groovy?
Answer-26: Use @Category annotation or metaclass extensions.
Question-27. What is the difference between == and is in Groovy?
Answer-27: == checks for equality, while is checks for reference equality.
Question-28. How do you read a file in Groovy?
Answer-28: Use new File("path").text or eachLine. Example: new File("test.txt").eachLine { println it }.
Question-29. How do you write to a file in Groovy?
Answer-29: Use new File("path").write("text").
Question-30. What is Groovy's default visibility modifier for classes?
Answer-30: The default is public.
Question-31. What are traits in Groovy?
Answer-31: Traits are reusable code units for multiple inheritance in classes.
Question-32. How do you define a trait in Groovy?
Answer-32: Use the trait keyword. Example: trait MyTrait { void method() { println "Trait Method" } }.
Question-33. What is the Expando class in Groovy?
Answer-33: Expando allows creating dynamic objects with properties and methods.
Question-34. What is the purpose of Groovy's metaClass?
Answer-34: metaClass provides runtime metaprogramming capabilities.
Question-35. What is the difference between String and GString in Groovy?
Answer-35: String is immutable, while GString supports interpolation and can be dynamic.
Question-36. How do you perform JSON parsing in Groovy?
Answer-36: Use groovy.json.JsonSlurper. Example: new JsonSlurper().parseText(jsonString).
Question-37. How do you perform XML parsing in Groovy?
Answer-37: Use groovy.util.XmlSlurper. Example: new XmlSlurper().parseText(xmlString).
Question-38. What are Groovy's standard collections?
Answer-38: Lists, Maps, Sets, and Ranges.
Question-39. What is the @Immutable annotation in Groovy?
Answer-39: @Immutable makes a class immutable, preventing modification of its fields.
Question-40. How do you define scripts with arguments in Groovy?
Answer-40: Use args array. Example: println args[0].
Question-41. What is Groovy's assert used for?
Answer-41: assert checks for conditions and throws an exception if the condition fails.
Question-42. What are DSLs in Groovy?
Answer-42: Domain-Specific Languages are specialized syntaxes built using Groovy's dynamic features.
Question-43. How do you declare enums in Groovy?
Answer-43: Use the enum keyword. Example: enum Day { MONDAY, TUESDAY }.
Question-44. What is Groovy's @Lazy annotation?
Answer-44: @Lazy initializes the annotated field only when it's accessed for the first time.
Question-45. What is Groovy's @Singleton annotation?
Answer-45: @Singleton ensures that a class has only one instance.
Question-46. How does Groovy handle default method parameters?
Answer-46: Default values can be specified. Example: def greet(name = "World") { println "Hello, $name" }.
Question-47. What is the @Builder annotation in Groovy?
Answer-47: @Builder generates a builder pattern for object creation.
Question-48. How do you add a custom method to a Groovy class at runtime?
Answer-48: Use the metaClass. Example: String.metaClass.reverseCase = { -> delegate.swapCase() }.
Question-49. What is Groovy's ConfigSlurper?
Answer-49: ConfigSlurper parses configuration files written in Groovy syntax.
Question-50. How do you integrate Groovy with Java?
Answer-50: Groovy classes can directly use Java classes, and Java classes can use Groovy classes with Groovy libraries.
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