Q:

How to install java locally - no root - on linux, if possible? 

I need java 1.7 and server has only got 1.6.  I have no root privileges.  I tried to google out something but it seems like nobody was doing it.  Can I somehow compile it or get ready binaries so I could put those into my PATH.  Could you help?  System is Redhat. 

A:

It is quite easy...
Download the JDK as a tarball from Oracle (a simple google search will yield the link). 
Unzip it somewhere in your $HOME (for instance, $HOME/jdk). 
Set JAVA_HOME to the path of the root JDK install; then prepend $JAVA_HOME/bin to your PATH. 
And off you go. 

Here I have a particular setting insofar as I run three different major versions of the JDK: 6, 7, 8.  For instance, here is my source file for setting the current shell to use Java 8:
$ cat ~/.jdk/8
export JAVA_HOME=/opt/sunjdk/1.8/current
export PATH="$JAVA_HOME/bin:$PATH"

And in /opt/sunjdk/1.8 (given that /opt/sunjdk is writable by my user hence I don't need to be root):
$ ls -l /opt/sunjdk/1.8/* -d
lrwxrwxrwx 1 fge fge  11 Oct 30 10:09 /opt/sunjdk/1.8/current -> jdk1.8.0_25
drwxr-xr-x 1 fge fge 274 Mar 18  2014 /opt/sunjdk/1.8/jdk1.8.0_05
drwxr-xr-x 1 fge fge 274 Sep 18 02:44 /opt/sunjdk/1.8/jdk1.8.0_25

(and yes, I was root to begin with so as to grant write permissions for /opt/sunjdk to "my" user; if you have no such liberty, just create another directory in your home)

A:

Oracle offers JRE and JDK also as *.tar.gz for Linux.  I usually had success just downloading such a package, untarring/unzipping it (tar -xzvf jdk-8u25.tar.gz) and then running it, using the absolute path. 

A:

I was able to accomplish this using conda. 
Conda is an open-source package-manager by Anaconda, that according to the website:

You do not need administrative or root permissions to install Anaconda if you select a user-writable install location. 

You can search the package repo from a browser at anaconda.org or command line, for example here are the results for JDK. 
For Linux, you would download this installer.   Here is a command line that will start the installer for convenience:
wget https://repo.anaconda.com/miniconda/Miniconda3-latest-Linux-x86_64.sh && bash Miniconda3-latest-Linux-x86_64.sh

Once conda is installed, you can install packages.  For example, to install the JetBrains Runtime OpenJDK build:
conda install -c anaconda openjdk

Other builds may be available from other channels in the repository. 
The instructions above should give a working install, but the Getting started guide is a good place to get started.   Conda uses the concept of environments to help manage versions and paths in a fairly simple and straightforward manner. 
I hope this helps someone.