Core Java Interview Questions and Answers
Question: Explain the usage of Java packages.Answer: 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.e.g. 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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