aindreas/uni
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Rename year directories to allow natural ordering

Browse Source
This commit is contained in:
Aindréas Ó hAodha
2023-12-20 03:57:27 +00:00
parent 0ab1f5ad3a
commit 1f7d812b98
1895 changed files with 0 additions and 7188 deletions
Download Patch File Download Diff File Expand all files Collapse all files

66
year2/semester1/logseq-stuff/pages/Introduction to Java.md Normal file
View File

@ -0,0 +1,66 @@
- #[[CT2106 - Object-Oriented Programming]]
- **Previous Topic:** [[Introduction to Object-Oriented Programming]]
- **Next topic:** [[First Java Code]]
- **Relevant Slides:** ![Lecture01.pdf](../assets/Lecture01_1662850796416_0.pdf)
-
- ## High-Level Language
- Both Java and C are **high-level languages** and Assembly is a **low-level language**.
- "**High-Level**" is a *relative* term.
- A **High-Level Language** is the level of abstraction above a **Low-Level Language**.
- A **Low-Level Language** has little or no abstraction over the machine code of a particular processor.
- ### Advantages of High-Level Programming Languages
- Easier to program.
- Syntax can be understood by people.
- Programs take less time to write, are shorter, & easier to read, so they are more likely to be correct.
- Portable - they can be run on different kinds of computers.
-
-
- ## Translating Your Code
- Unless you are writing Machine Code, your code has to be translated into machine code to be run on your computer.
- There are two types of translation:
- 1. **Compilation**.
2. **Interpretation**
-
- ### Compilation
- What is a **Compiler**? #card
card-last-interval:: 33.64
card-repeats:: 4
card-ease-factor:: 2.9
card-next-schedule:: 2022-12-18T07:44:08.310Z
card-last-reviewed:: 2022-11-14T16:44:08.310Z
card-last-score:: 5
- A **compiler** is a program that takes human-readable source code and translates it in one go into Machine Code.
- With compilation, "translation" occurs ^^before the program is run.^^
- Machine Code generated by compilation is **not portable**.
- However, the generated Machine Code typically executes **very efficiently**.
- For big projects, the compile time can be slow.
- ### Interpretation
- Code is "translated"" on-the-fly at runtime into commands that can be executed on the machine.
- Code is read & executed by the **interpreter** when the program is run.
- Interpreted code is **portable** (as long as there is an interpreter).
- Typically, interpreted code is ^^slower to run^^ as each statement has to be interpreted into machine code **on-the-fly**.
- Greater chance of run-time errors.
-
- ^^Java is typically both *compiled* **and** *interpreted*.^^
- ^^Java is **compiled** to *Byte Code* - an *intermediate language* which is portable.^^
- ^^This Byte Code is then **read** and **executed** by a Java **interpreter**.^^
-
-
- ## Java Virtual Machine (JVM)
- What is the **JVM**? #card
card-last-interval:: 33.64
card-repeats:: 4
card-ease-factor:: 2.9
card-next-schedule:: 2022-12-18T07:38:43.908Z
card-last-reviewed:: 2022-11-14T16:38:43.909Z
card-last-score:: 5
- The **Java Virtual Machine (JVM)** is a piece of software - a *virtual computer* upon which **Java byte code** is executed.
- What is the **JRE**? #card
card-last-interval:: 28.3
card-repeats:: 4
card-ease-factor:: 2.66
card-next-schedule:: 2022-12-12T23:43:23.817Z
card-last-reviewed:: 2022-11-14T16:43:23.818Z
card-last-score:: 3
- The **Java Runtime Environment (JRE)** contains the JVM and all the libraries required to run the Java progam.
-