Synechron Java Software Developer Interview Questions, Process, and Tips

Run time polymorphism is method overriding while compile time polymorphism is method overloading.

• Compile time polymorphism is resolved at compile time while run time polymorphism is resolved at runtime.

• Method overloading is an example of compile time polymorphism while method overriding is an example of run time polymorphism.

• Compile time polymorphism is faster than run time polymorphism as it is resolved at compile tim...read more

HashMap is a data structure that stores key-value pairs and provides constant time complexity for basic operations.

• HashMap uses hashing to store and retrieve elements

• It allows null values and only one null key

• Collisions are resolved using separate chaining or open addressing

• The initial capacity and load factor can be specified during initialization

• The size of the HashMap is dynamically increased as elements are added

Exceptions in Rest APIs are handled using try-catch blocks and appropriate error responses.

• Use try-catch blocks to catch exceptions that may occur during API execution.

• Handle different types of exceptions separately to provide specific error responses.

• Return appropriate HTTP status codes and error messages in the response.

• Log the exception details for debugging purposes.

• Consider using a global exception handler to cent

The highest limit of HashMap is Integer.MAX_VALUE, which is 2^31 - 1.

• The highest limit is determined by the maximum capacity of an array in Java, which is Integer.MAX_VALUE.

• The default initial capacity of a HashMap is 16, and it automatically increases its capacity as needed.

• If the number of elements exceeds the maximum capacity, an OutOfMemoryError will be thrown.

Functional interfaces are interfaces with only one abstract method. They are used for lambda expressions and method references.

• Functional interfaces are used for functional programming in Java.

• They are used for lambda expressions and method references.

• They have only one abstract method.

• Examples of functional interfaces are Runnable, Callable, and Comparator.

• Functional interfaces can be annotated with @FunctionalInterfa

Streams in Java are a sequence of elements that can be processed in parallel or sequentially.

• Streams are used to perform operations on collections of data in a concise and functional way.

• They can be used to filter, map, reduce, and sort data.

• Streams can be processed in parallel to improve performance.

• Examples of stream methods include filter(), map(), reduce(), and sorted().

To convert list to arraylist, use ArrayList constructor. To convert arraylist to list, use List constructor.

• To convert list to arraylist, use ArrayList constructor and pass the list as parameter.

• To convert arraylist to list, use List constructor and pass the arraylist as parameter.

• Example: List list = Arrays.asList("one", "two", "three");

• ArrayList arrayList = new ArrayList<>(list);

• Example: ArrayList arrayList = new Arr...read more