Core Java Interview Questions and Answers
Ques. Explain the usage of Java packages.Ans. This is a way to organize files when a project consists of multiple modules. It also helps resolve naming conflicts when different packages have classes with the same names. Packages access level also allows you to protect data from being used by the non-authorized classes.
java.lang — basic language functionality and fundamental types
java.util — collection data structure classes
java.io — file operations
java.math — multiprecision arithmetics
java.nio — the New I/O framework for Java
java.net — networking operations, sockets, DNS lookups
java.security — key generation, encryption and decryption
java.sql — Java Database Connectivity (JDBC) to access databases
java.awt — basic hierarchy of packages for native GUI components
javax.swing — hierarchy of packages for platform-independent rich GUI components
java.applet — classes for creating an applet
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