https://wiki.christofbuechi.ch/index.php?action=history&feed=atom&title=Chapter_1Chapter 1 - Versionsgeschichte2026-08-24T16:57:16ZVersionsgeschichte dieser Seite in wikiMediaWiki 1.29.1https://wiki.christofbuechi.ch/index.php?title=Chapter_1&diff=141&oldid=prevSusi: Die Seite wurde neu angelegt: «= Chapter 1 = ==Objectives== === Java Basics === * Define the scope of variables * Define the structure of a Java class * Create executable Java applications, Ru…»2016-11-28T22:59:08Z<p>Die Seite wurde neu angelegt: «= Chapter 1 = ==Objectives== === Java Basics === * Define the scope of variables * Define the structure of a Java class * Create executable Java applications, Ru…»</p>
<p><b>Neue Seite</b></p><div>= Chapter 1 =<br />
==Objectives==<br />
=== Java Basics ===<br />
* Define the scope of variables<br />
* Define the structure of a Java class<br />
* Create executable Java applications, Run a Java program from command line<br />
* Import other Java packages<br />
* Compare and contrast features and components of Java<br />
=== Working with Java Data Types===<br />
* Declare and initialize variables<br />
* Difference between object reference variables and primitive variables<br />
* know how to read and write to object fields<br />
* explain an objects lifecycle<br />
(creation, "dereference by reassignment", garbage collection)<br />
* develop code that uses wrapper classes<br />
(Boolean, Double, Integer)<br />
<br />
==scopes==<br />
==structure==<br />
Java classes have two primary elements: methods and fields.<br />
* fields/variables: hold a state of the program<br />
* methods: operate on the state<br />
<br />
1 file = 1 class, if you have two classes, 1 must bi public an match the filename, other class can be private but not public too<br />
<br />
classes are logical grouped into packages<br />
<br />
if package starts with java or javax, this means it came with the JDK<br />
packages names are mostly letters and numbers separated by dots.<br />
<br />
wildcards for matching all classes in the same package<br />
(not every class in the package is imported, the compiler figures out what's actually needed)<br />
<br />
a wildcard only matches class names, not "fie.Files* -> import java.nio.*; not possbile<br />
only one wildcard is possible in an import-statement<br />
<br />
<br />
package java.lang is automatically imported, you can type this package as an import statement, but you don't have to<br />
<br />
default package, is a special unnamed package that you should use only for throwaway code<br />
<br />
java looks in the current package for other classes.<br />
<br />
<br />
==compare and contrast features and components==<br />
==declare and initialize variables==<br />
==object variables vs. primitive variables==<br />
==read and write object fields==<br />
==object lifecycle==<br />
==wrapper classes==<br />
==imports==<br />
<br />
<br />
===main method===<br />
String[] args, String args[], String ... args<br />
are all correct</div>Susi