I am currently taking a course on Compilers. I don't like the idea of blindly memorising facts without any sort of place to apply them to. I want to learn by hands-on doing. 
So, I would like to have the complete code of 3-4 compilers, possibly for languages with different syntax rules (python,c, c++, java) while working through the Dragon book.
If complete compilers are too much of an ask, examples of parsers(well-written LL, LR, LALR parsers) and intermediate-code generators for these languages would also do. 
There is a LOT of code out there on the Internet regarding this, but I want something that is considered to be high-quality and standard. I would be grateful for any resources that you can refer me to in this matter. Thanks.
Your course on compilers should be giving you the pieces that will eventually lead to a full blown compiler.  
For example, the section on lexical analysis can lead to a component called the Lexer.  If you keep an eye open to generics and re-usability, you can turn this into a component that can be used later in your compiler.
I highly suggest you take the approach of having at least two components in every homework project:  main and the library component.  In the example of lexical analysis, the main component would handle input and testing.  The library component would be the lexer.  This technique will help greatly after you graduate and develop huge applications in the real world.
Good source code for compiler components