INSTALLATION NOTES :
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STEP 1 :
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sudo apt-get update
STEP 2 :
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sudo apt-get install default-jre
STEP 3 :
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sudo apt-get install default-jdk
STEP 4 :
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add Oracle's PPA, then update your package repository.
sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
STEP 5 :
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sudo apt-get install oracle-java8-installer
STEP 6 :
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check java versions
java -version