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Java Error & Exceptions
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- Java - throw Exception
- Java - Exception Propagation
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Java Multithreading
- Java - Multithreading
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- Java - Joining Threads
- Java - Naming Thread
- Java - Thread Scheduler
- Java - Thread Pools
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- Java - Thread Priority
- Java - Daemon Threads
- Java - Thread Group
- Java - Shutdown Hook
Java Synchronization
- Java - Synchronization
- Java - Block Synchronization
- Java - Static Synchronization
- Java - Inter-thread Communication
- Java - Thread Deadlock
- Java - Interrupting a Thread
- Java - Thread Control
- Java - Reentrant Monitor
Java Networking
- Java - Networking
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- Java - URL Processing
- Java - URL Class
- Java - URLConnection Class
- Java - HttpURLConnection Class
- Java - Socket Class
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Java Collections
Java List Interface
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Java Map Interface
- Java - Map Interface
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- Java - The IdentityHashMap Class
Java Set Interface
- Java - Set Interface
- Java - HashSet
- Java - EnumSet
- Java - LinkedHashSet
- Java - SortedSet Interface
- Java - TreeSet
Java Data Structures
- Java - Data Structures
- Java - Enumeration
- Java - BitSet Class
- Java - Dictionary
- Java - Hashtable
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Java Collections Algorithms
Java Miscellaneous
- Java - Recursion
- Java - Regular Expressions
- Java - Serialization
- Java - Strings
- Java - Array Methods
Advanced Java
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Compact Number Formatting
Java APIs & Frameworks
Java Useful Resources
- Java - Loop Control
- Java - Decision Making
- Java - If-else
- Java - Switch
- Java - For Loops
- Java - For-Each Loops
- Java - While Loops
- Java - do-while Loops
- Java - Break
- Java - Continue
Object Oriented Programming
- Java - OOPs Concepts
- Java - Object & Classes
- Java - Class Attributes
- Java - Class Methods
- Java - Methods
- Java - Variables Scope
- Java - Constructors
- Java - Access Modifiers
- Java - Inheritance
- Java - Aggregation
- Java - Polymorphism
- Java - Overriding
- Java - Method Overloading
- Java - Dynamic Binding
- Java - Static Binding
- Java - Instance Initializer Block
- Java - Abstraction
- Java - Encapsulation
- Java - Interfaces
- Java - Packages
- Java - Inner Classes
- Java - Static Class
- Java - Anonymous Class
- Java - Singleton Class
- Java - Wrapper Classes
- Java - Enums
- Java - Enum Constructor
- Java - Enum Strings
Java Built-in Classes
Java File Handling
- Java - Files
- Java - Create a File
- Java - Write to File
- Java - Read Files
- Java - Delete Files
- Java - Directories
- Java - I/O Streams
Java Error & Exceptions
- Java - Exceptions
- Java - try-catch Block
- Java - try-with-resources
- Java - Multi-catch Block
- Java - Nested try Block
- Java - Finally Block
- Java - throw Exception
- Java - Exception Propagation
- Java - Built-in Exceptions
- Java - Custom Exception
Java Multithreading
- Java - Multithreading
- Java - Thread Life Cycle
- Java - Creating a Thread
- Java - Starting a Thread
- Java - Joining Threads
- Java - Naming Thread
- Java - Thread Scheduler
- Java - Thread Pools
- Java - Main Thread
- Java - Thread Priority
- Java - Daemon Threads
- Java - Thread Group
- Java - Shutdown Hook
Java Synchronization
- Java - Synchronization
- Java - Block Synchronization
- Java - Static Synchronization
- Java - Inter-thread Communication
- Java - Thread Deadlock
- Java - Interrupting a Thread
- Java - Thread Control
- Java - Reentrant Monitor
Java Networking
- Java - Networking
- Java - Socket Programming
- Java - URL Processing
- Java - URL Class
- Java - URLConnection Class
- Java - HttpURLConnection Class
- Java - Socket Class
- Java - Generics
Java Collections
Java List Interface
Java Queue Interface
Java Map Interface
- Java - Map Interface
- Java - HashMap
- Java - LinkedHashMap
- Java - WeakHashMap
- Java - EnumMap
- Java - SortedMap Interface
- Java - TreeMap
- Java - The IdentityHashMap Class
Java Set Interface
- Java - Set Interface
- Java - HashSet
- Java - EnumSet
- Java - LinkedHashSet
- Java - SortedSet Interface
- Java - TreeSet
Java Data Structures
- Java - Data Structures
- Java - Enumeration
- Java - BitSet Class
- Java - Dictionary
- Java - Hashtable
- Java - Properties
Java Collections Algorithms
Java Miscellaneous
- Java - Recursion
- Java - Regular Expressions
- Java - Serialization
- Java - Strings
- Java - Array Methods
Advanced Java
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Compact Number Formatting
Java APIs & Frameworks
Java Useful Resources
Java File Handling
- Java - Files
- Java - Create a File
- Java - Write to File
- Java - Read Files
- Java - Delete Files
- Java - Directories
- Java - I/O Streams
Java Error & Exceptions
- Java - Exceptions
- Java - try-catch Block
- Java - try-with-resources
- Java - Multi-catch Block
- Java - Nested try Block
- Java - Finally Block
- Java - throw Exception
- Java - Exception Propagation
- Java - Built-in Exceptions
- Java - Custom Exception
Java Multithreading
- Java - Multithreading
- Java - Thread Life Cycle
- Java - Creating a Thread
- Java - Starting a Thread
- Java - Joining Threads
- Java - Naming Thread
- Java - Thread Scheduler
- Java - Thread Pools
- Java - Main Thread
- Java - Thread Priority
- Java - Daemon Threads
- Java - Thread Group
- Java - Shutdown Hook
Java Synchronization
- Java - Synchronization
- Java - Block Synchronization
- Java - Static Synchronization
- Java - Inter-thread Communication
- Java - Thread Deadlock
- Java - Interrupting a Thread
- Java - Thread Control
- Java - Reentrant Monitor
Java Networking
- Java - Networking
- Java - Socket Programming
- Java - URL Processing
- Java - URL Class
- Java - URLConnection Class
- Java - HttpURLConnection Class
- Java - Socket Class
- Java - Generics
Java Collections
Java List Interface
Java Queue Interface
Java Map Interface
- Java - Map Interface
- Java - HashMap
- Java - LinkedHashMap
- Java - WeakHashMap
- Java - EnumMap
- Java - SortedMap Interface
- Java - TreeMap
- Java - The IdentityHashMap Class
Java Set Interface
- Java - Set Interface
- Java - HashSet
- Java - EnumSet
- Java - LinkedHashSet
- Java - SortedSet Interface
- Java - TreeSet
Java Data Structures
- Java - Data Structures
- Java - Enumeration
- Java - BitSet Class
- Java - Dictionary
- Java - Hashtable
- Java - Properties
Java Collections Algorithms
Java Miscellaneous
- Java - Recursion
- Java - Regular Expressions
- Java - Serialization
- Java - Strings
- Java - Array Methods
Advanced Java
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Compact Number Formatting
Java APIs & Frameworks
Java Useful Resources
- Java - Exceptions
- Java - try-catch Block
- Java - try-with-resources
- Java - Multi-catch Block
- Java - Nested try Block
- Java - Finally Block
- Java - throw Exception
- Java - Exception Propagation
- Java - Built-in Exceptions
- Java - Custom Exception
Java Multithreading
- Java - Multithreading
- Java - Thread Life Cycle
- Java - Creating a Thread
- Java - Starting a Thread
- Java - Joining Threads
- Java - Naming Thread
- Java - Thread Scheduler
- Java - Thread Pools
- Java - Main Thread
- Java - Thread Priority
- Java - Daemon Threads
- Java - Thread Group
- Java - Shutdown Hook
Java Synchronization
- Java - Synchronization
- Java - Block Synchronization
- Java - Static Synchronization
- Java - Inter-thread Communication
- Java - Thread Deadlock
- Java - Interrupting a Thread
- Java - Thread Control
- Java - Reentrant Monitor
Java Networking
- Java - Networking
- Java - Socket Programming
- Java - URL Processing
- Java - URL Class
- Java - URLConnection Class
- Java - HttpURLConnection Class
- Java - Socket Class
- Java - Generics
Java Collections
Java List Interface
Java Queue Interface
Java Map Interface
- Java - Map Interface
- Java - HashMap
- Java - LinkedHashMap
- Java - WeakHashMap
- Java - EnumMap
- Java - SortedMap Interface
- Java - TreeMap
- Java - The IdentityHashMap Class
Java Set Interface
- Java - Set Interface
- Java - HashSet
- Java - EnumSet
- Java - LinkedHashSet
- Java - SortedSet Interface
- Java - TreeSet
Java Data Structures
- Java - Data Structures
- Java - Enumeration
- Java - BitSet Class
- Java - Dictionary
- Java - Hashtable
- Java - Properties
Java Collections Algorithms
Java Miscellaneous
- Java - Recursion
- Java - Regular Expressions
- Java - Serialization
- Java - Strings
- Java - Array Methods
Advanced Java
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Compact Number Formatting
Java APIs & Frameworks
Java Useful Resources
- Java - Synchronization
- Java - Block Synchronization
- Java - Static Synchronization
- Java - Inter-thread Communication
- Java - Thread Deadlock
- Java - Interrupting a Thread
- Java - Thread Control
- Java - Reentrant Monitor
Java Networking
- Java - Networking
- Java - Socket Programming
- Java - URL Processing
- Java - URL Class
- Java - URLConnection Class
- Java - HttpURLConnection Class
- Java - Socket Class
- Java - Generics
Java Collections
Java List Interface
Java Queue Interface
Java Map Interface
- Java - Map Interface
- Java - HashMap
- Java - LinkedHashMap
- Java - WeakHashMap
- Java - EnumMap
- Java - SortedMap Interface
- Java - TreeMap
- Java - The IdentityHashMap Class
Java Set Interface
- Java - Set Interface
- Java - HashSet
- Java - EnumSet
- Java - LinkedHashSet
- Java - SortedSet Interface
- Java - TreeSet
Java Data Structures
- Java - Data Structures
- Java - Enumeration
- Java - BitSet Class
- Java - Dictionary
- Java - Hashtable
- Java - Properties
Java Collections Algorithms
Java Miscellaneous
- Java - Recursion
- Java - Regular Expressions
- Java - Serialization
- Java - Strings
- Java - Array Methods
Advanced Java
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Compact Number Formatting
Java APIs & Frameworks
Java Useful Resources
Java List Interface
Java Queue Interface
Java Map Interface
- Java - Map Interface
- Java - HashMap
- Java - LinkedHashMap
- Java - WeakHashMap
- Java - EnumMap
- Java - SortedMap Interface
- Java - TreeMap
- Java - The IdentityHashMap Class
Java Set Interface
- Java - Set Interface
- Java - HashSet
- Java - EnumSet
- Java - LinkedHashSet
- Java - SortedSet Interface
- Java - TreeSet
Java Data Structures
- Java - Data Structures
- Java - Enumeration
- Java - BitSet Class
- Java - Dictionary
- Java - Hashtable
- Java - Properties
Java Collections Algorithms
Java Miscellaneous
- Java - Recursion
- Java - Regular Expressions
- Java - Serialization
- Java - Strings
- Java - Array Methods
Advanced Java
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Compact Number Formatting
Java APIs & Frameworks
Java Useful Resources
Java Map Interface
- Java - Map Interface
- Java - HashMap
- Java - LinkedHashMap
- Java - WeakHashMap
- Java - EnumMap
- Java - SortedMap Interface
- Java - TreeMap
- Java - The IdentityHashMap Class
Java Set Interface
- Java - Set Interface
- Java - HashSet
- Java - EnumSet
- Java - LinkedHashSet
- Java - SortedSet Interface
- Java - TreeSet
Java Data Structures
- Java - Data Structures
- Java - Enumeration
- Java - BitSet Class
- Java - Dictionary
- Java - Hashtable
- Java - Properties
Java Collections Algorithms
Java Miscellaneous
- Java - Recursion
- Java - Regular Expressions
- Java - Serialization
- Java - Strings
- Java - Array Methods
Advanced Java
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Compact Number Formatting
Java APIs & Frameworks
Java Useful Resources
- Java - Set Interface
- Java - HashSet
- Java - EnumSet
- Java - LinkedHashSet
- Java - SortedSet Interface
- Java - TreeSet
Java Data Structures
- Java - Data Structures
- Java - Enumeration
- Java - BitSet Class
- Java - Dictionary
- Java - Hashtable
- Java - Properties
Java Collections Algorithms
Java Miscellaneous
- Java - Recursion
- Java - Regular Expressions
- Java - Serialization
- Java - Strings
- Java - Array Methods
Advanced Java
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Compact Number Formatting
Java APIs & Frameworks
Java Useful Resources
Java Miscellaneous
- Java - Recursion
- Java - Regular Expressions
- Java - Serialization
- Java - Strings
- Java - Array Methods
Advanced Java
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Compact Number Formatting
Java APIs & Frameworks
Java Useful Resources
- Java - Command-Line Arguments
- Java - Lambda Expressions
- Java - Sending Email
- Java - Applet Basics
- Java - Javadoc Comments
- Java - Autoboxing and Unboxing
- Java - File Mismatch Method
- Java - REPL (JShell)
- Java - Multi-Release Jar Files
- Java - Private Interface Methods
- Java - Inner Class Diamond Operator
- Java - Multiresolution Image API
- Java - Collection Factory Methods
- Java - Module System
- Java - Nashorn JavaScript
- Java - Optional Class
- Java - Method References
- Java - Functional Interfaces
- Java - Default Methods
- Java - Base64 Encode Decode
- Java - Switch Expressions
- Java - Teeing Collectors
- Java - Microbenchmark
- Java - Text Blocks
- Java - Null Pointer Exception
- Java - Packaging Tools
- Java - Sealed Classes
- Java - Record Classes
- Java - Hidden Classes
- Java - Compact Number Formatting
Java APIs & Frameworks
Java Useful Resources
Java 8 Mock Test
This section presents you various set of Mock Tests related to Java 8. You can download these sample mock tests at your local machine and solve offline at your convenience. Every mock test is supplied with a mock test key to let you verify the final score and grade yourself.
Java 8 Mock Test IV
Q 1 - Which of the following method of Base64 class returns a Base64.Encoder that encodes using the URL and Filename safe type base64 encoding scheme?
Answer : B
Explanation
getUrlEncoder() method of Base64 class returns a Base64.Encoder that encodes using the URL and Filename safe type base64 encoding scheme.
Q 2 - Which of the following is the correct lambda expression which add two numbers and return their sum?
Answer : C
Explanation
Both of the above options are correct.
Q 3 - Which of the following is the correct lambda expression which add two numbers and return their sum?
A - (int a, int b) -> { return a + b;};
Answer : C
Explanation
Both of the above options are correct.
Q 4 - Lambda expressions are used primarily to define inline implementation of a functional interface.
Answer : A
Explanation
Lambda expressions are used primarily to define inline implementation of a functional interface.
Q 5 - Using lambda expression, you can refer to final variable or effectively final variable (which is assigned only once).
Answer : B
Explanation
Using lambda expression, you can refer to final variable or effectively final variable (which is assigned only once).
Answer : A
Explanation
Method references help to point to methods by their names.
Answer : B
Explanation
A method reference is described using :: (double colon) symbol.
Answer : B
Explanation
Functional interfaces have a single functionality to exhibit.
Q 9 - A stream provides a set of elements of specific type in a sequential manner.
Answer : A
Explanation
A stream provides a set of elements of specific type in a sequential manner. A stream gets/computes elements on demand. It never stores the elements.
Answer : A
Explanation
Stream takes Collections, Arrays, or I/O resources as input source.
Q 11 - Stream supports aggregate operations like filter, map, limit, reduce, find and match.
Answer : B
Explanation
Stream supports aggregate operations like filter, map, limit, reduce, find, match, and so on.
Q 12 - Most of the stream operations return stream itself so that their result can be pipelined.
Answer : B
Explanation
Most of the stream operations return stream itself so that their result can be pipelined.
Q 13 - Stream operations do the iterations internally over the source elements provided.
Answer : B
Explanation
Stream operations do the iterations internally over the source elements provided, in contrast to Collections where explicit iteration is required.
Answer : A
Explanation
Optional is a container object which is used to contain not-null objects.
Answer : B
Explanation
Optional object is used to represent null with absent value.
Answer : A
Explanation
Optional.ofNullable method allows passed parameter to be null.
Q 17 - Optional.of method throws NullPointerException if passed parameter is null.
Answer : A
Explanation
Optional.of method throws NullPointerException if passed parameter is null.
Answer : B
Explanation
Optional.isPresent method checks the value is present or not.
Q 19 - Optional.orElse method returns the value if present otherwise returns the default value passed.
Answer : B
Explanation
Optional.orElse method returns the value if present otherwise returns the default value passed.
Answer : B
Explanation
Optional.get method gets the value, value should be present.
Q 21 - java.util.Date is not thread safe, thus developers have to deal with concurrency issue while using date.
Answer : A
Explanation
java.util.Date is not thread safe, thus developers have to deal with concurrency issue while using date.
Q 22 - The new date-time API in java 8 is immutable and does not have setter methods.
Answer : A
Explanation
The new date-time API in java 8 is immutable and does not have setter methods.
Q 23 - In which of the following type of Base64 encoding, Output is mapped to a set of characters lying in A-Za-z0-9+/?
Answer : A
Explanation
Simple − Output is mapped to a set of characters lying in A-Za-z0-9+/.
Q 24 - In which of the following type of Base64 encoding, Output is mapped to a set of characters lying in A-Za-z0-9+_?
Answer : B
Explanation
URL − Output is mapped to a set of characters lying in A-Za-z0-9+_.
Q 25 - In which of the following type of Base64 encoding, Output is mapped to MIME friendly format?
Answer : C
Explanation
MIME − Output is mapped to MIME friendly format. Output is represented in lines of no more than 76 characters each, and uses a carriage return ' ' followed by a linefeed ' ' as the line separator. No line separator is present to the end of the encoded output.
Answer Sheet
Question Number | Answer Key |
---|---|
1 | B |
2 | C |
3 | C |
4 | A |
5 | B |
6 | A |
7 | B |
8 | B |
9 | A |
10 | A |
11 | B |
12 | B |
13 | B |
14 | A |
15 | B |
16 | A |
17 | A |
18 | B |
19 | B |
20 | B |
21 | A |
22 | A |
23 | A |
24 | B |
25 | C |