To install/add JRE Follow below Steps
1. Go to Window -> preferences -> type “installed”
2. Click on Add button -> standard VM -> Next
3. Click on Directory -> Browse you installed java folder and select jdk or jre folder
4. click on finish button you will see new jre in list
1. Right click on project-> Properties->type “java build path”
2. Click on Edit button and change jre from alternate jre -> click finish->ok.