Install JDK and Eclipse

Get the Android SDK

Eclipse is just one of the numerous script editing applications for developing java programs and allows students to write and compile java code and execute programs.

First Way..

1. Visit the Java downloads page on Oracle's website to find the JDK environment download. Here..
2. Once you have selected download, accept the terms of service and choose the correct OS corresponding for the specific JDK. (Windows, Mac, Linux, etc.)
3. Install Java SE Development Kit
4. When the installation is finished, we will begin to the installation of Eclipse. Go to http://www.eclipse.org/downloads/.

Releases

• Mars Packages
• Luna Packages
• Kepler Packages
• Juno Packages
• Indigo Packages
• Helios Packages
• Galileo Packages
• Ganymede Packages
• Europa Packages
• All Releases

Second way

How to build android application you can use ADT bundle.

The Android SDK provides the API libraries and developer tools necessary to build, test, and debug apps for Android.
Download the ADT Bundle to quickly start developing apps. It includes the essential Android SDK components and a version of the Eclipse IDE with built-in ADT (Android Developer Tools) to streamline your Android app development.

With a single download, the Eclipse ADT bundle includes everything you need to begin developing apps:

• Eclipse + ADT plugin
• Android SDK Tools
• Android Platform-tools
• A version of the Android platform
• A version of the Android system image for the emulator

Just visit this link and Download Eclipse ADT bundle

More reference about How to Download, Install, and Run JDK and Eclipse
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