View source for Java10/Examples



This is an informal page listing examples of features that are implemented by the [https://marketplace.eclipse.org/content/java-10-support-oxygen Java 10 Support for Oxygen]. You are welcome to try out these examples. If you find bugs, please file a bug after checking for a duplicate entry [https://bugs.eclipse.org/bugs/buglist.cgi?cmdtype=dorem&list_id=17341573&namedcmd=J10.Open&remaction=run&sharer_id=152344 here].


{| class="wikitable"

! scope="row" style="width: 15%;" |
| style="width: 60%; text-align: center" | '''Feature''' / Steps
! style="width: 25%;" | Expected Result
|-
! colspan="3" | The Pre-requisite: Java 10 JRE Support
|-
! scope="row" | Add Java 10 JRE
| Use Window -> Preferences-> Java -> Installed JREs -> Add... <br>
<br>
[[File:FileAddJ10.jpg]]
<br>
[note: Eclipse -> Preferences in Mac / Window -> Preferences in Windows]
| Java 10 JRE recognized as a valid JRE
|-
! scope="row" | Project JRE
| In Package Explorer Use project's context menu and add Java 10 JRE  || JRE specific (eg Object) gets resolved in the project.
|-
! scope="row" | Package Explorer
| Go to Package Explorer and expand the Java 10 JRE || Modules (eg java.base etc) are listed in the package explorer view
|-
! colspan="3" | The First Step: Java 10 Compliance
|-
! scope="row" | Set Project Compliance in Package Explorer
| Context Menu of Project -> Properties -> Set project-specific, drop down to 10
<br>
<br>
[[File:j10.compliance.jpg]]
| No compiler errors
|-
! colspan="3" | Basic Necessity : Compilation and Error Reporting
|-
! scope="row" | Positive Compilation
| Use the following code:
<source lang="java">
package packvar;

import java.util.ArrayList;
import java.util.List;

public class VarUsage {
	public static void main(String[] args) {
		String s = new String("Hello World");
				
		var x = s; // var allowed in the variable declaration
		System.out.println(x);
		
		List<String> l = new ArrayList<>();
		l.add("List.Hello");
		for (var lx : l) { // var allowed in enhanced for loop
			System.out.println(lx);
		}
	}
}
</source> 

<br>
<br>
[[File:var.compile.jpg]]
| Code compiles
|-
! scope="row" | Compiler Error Cases
| 
<source lang="java">
package packvar;

public class VarError {
  public static void main(String[] args) {
    String s = new String("Hello");
    var x; // compiler error: Cannot use 'var' on variable without  initializer	
    var y = null; // compiler error: Cannot infer type for local variable initialized to 'null'	
  }
}
</source>
| Compiler errors are shown
|-
! colspan="3" | Essential Utilities: Code Completion, Hover and Quick Fix.
|-
! scope="row" | Basic context based var completion
| 
<br>
<br>
<source lang="java">
package packvar;

public class VarComplete {
  public static void main(String[] args) {
	String s = new String("hello");
	
	va // try completing here
}
}
</source>
[[File:var.complete.jpg]]
| Completes var since the place is appropriate
|-
! scope="row" | Negative Case - no completion
| 
<br>
<source lang="java">
package packvar;

public class VarComplete {
	va // complete here - 'var' not offered as a completion candidate
}
</source>
<br>
[[File:var.nocomplete.jpg]]
| Does not offer 'var' as completion
|-
! scope="row" | Hover 
| 
Hover over var to see the javadoc of the associated type (in this case : String) being displayed.
<br>
<source lang="java">
package packvar;
public class VarComplete {	
  public static void main(String[] args) {
	String s = new String("hello");
	var x = s;
	System.out.println(x);
  }
}
</source>
<br>
[[File:var.hover.jpg]]
| Shows javadoc of the type associated with var
|-
! scope="row" | Quick Assist : var to type 
| 
<br>
<source lang="java">
package packvar;
public class VarComplete {	
  public static void main(String[] args) {
	String s = new String("hello");
	var x = s;
	System.out.println(x);
  }
}
</source>
<br>
[[File:var.vartotype.jpg]]
| Provides option to change from var to type
|-
! scope="row" | Quick Assist: type to var 
| 
<br>
<source lang="java">
package packvar;
public class VarComplete {	
  public static void main(String[] args) {
	String s = new String("hello");
	String x = s;
	System.out.println(x);
  }
}
</source>
<br>
[[File:var.typetovar.jpg]]
| Provides option to change from type to var
|-
! colspan="3" | More to come in Java 11 !
|}