S Connor

Hi,
I've made a program to write to a .txt file.  Unfortunately the program is adding some strange symbols.  Can you please explain how to solve this problem?  I have included the program and the output below.

package com.mycompany.testopenfiletest; /** * * @author montk */ public class TestOpenFileTest {    public static void main(String[] args) {        System.out.println("Hello World!");        CreateSequentialFile csf = new CreateSequentialFile();        csf.openFile("testfile.txt");        csf.updateTextFile("testing update.");        csf.closeFile();    } } import java.io.FileOutputStream; import java.io.IOException; import java.io.ObjectOutputStream; import java.util.NoSuchElementException; import java.util.Scanner;         /** * * @author montk */ public class CreateSequentialFile {    private ObjectOutputStream output;        public void openFile( String fileName )    {        try        {            output = new ObjectOutputStream( new FileOutputStream( fileName ));        }        catch ( IOException ioException )        {            System.err.println( "Error opening file");        }    }        public void updateTextFile( String updateString )    {        try        {        output.writeObject( updateString );        }        catch ( IOException ioexception )        {            System.err.println( "Error writing to file" );        }        catch ( NoSuchElementException elementException )        {            System.err.println( "Invalid input please try again");        }    }        public void closeFile()    {        try        {            if ( output != null )                output.close();                    }        catch ( IOException ioException )        {            System.err.println( "Error closing file" );            System.exit( 1 );        }    } }

The output looks like this:
’ t testing update.

Hi,
I'm working through a java textbook and I came across this exercise which has an infinity sign.  I have attached a picture.  Could you tell me what it means please?

Thanks.  Do you know how I could rotate or reflect the image somehow?

Hi,

I want to make a project that will draw a kaleidoscope. I would need to draw some shapes inside a triangle and then reflect that triangle in six directions to make a hexagonal display.

I don't know how to draw shapes within a triangle so that any part of the shape that extends beyond the boundary is not drawn and I don't know how to reflect the shapes to make a hexagon.

Can you give me any tips please?

This worked for me, just had to increase the thread sleep time. Thanks very much

Lou Hamers wrote:

(You can just throw the InterruptedException from main() for the test.)

Can you explain how I would do that please?

I tried removing the / character as you suggested. Unfortunately, the sound file still does not play.

I've tried changing the file name to

AudioClip plonkSound = new AudioClip("file:///C:/Users/montk/OneDrive/Documents/NetBeansProjects/Ch_21/AudioClipTest/myaudio.wav");

still no luck.

Hi,
I'm trying to play an audio file using AudioClip.  The project compiles but no sound will play.  Can you advise me what the problem could be?

package com.mycompany.soundtest; import javafx.scene.media.Media; import javafx.scene.media.AudioClip; import java.nio.file.Paths; /** * * @author montk */ public class SoundTest {    public static void main(String[] args) {        System.out.println("Hello World!");        AudioClip plonkSound = new AudioClip("file:/C:/Users/montk/OneDrive/Documents/NetBeansProjects/Ch_21/AudioClipTest/myaudio.wav");                plonkSound.play();    } }

I think that the issue has been resolved.

Can you tell me whether the method Audioclip I was trying to use is a method from java applets which are no longer being used? (I apologise if I am using the wrong terminology).

I added the dependency after you told me to.

When I select clean and build I get the following:

cd C:\Users\montk\OneDrive\Documents\NetBeansProjects\SoundTest; "JAVA_HOME=C:\\Program Files\\Java\\jdk-18.0.2.1" cmd /c "\"C:\\Program Files\\NetBeans-14\\netbeans\\java\\maven\\bin\\mvn.cmd\" \"-Dmaven.ext.class.path=C:\\Program Files\\NetBeans-14\\netbeans\\java\\maven-nblib\\netbeans-eventspy.jar\" clean install"
Scanning for projects...

-----------------< com.mycompany.soundtest:SoundTest >------------------
Building SoundTest 1.0-SNAPSHOT
--------------------------------[ jar ]---------------------------------

--- maven-clean-plugin:2.5:clean (default-clean) @ SoundTest ---
Deleting C:\Users\montk\OneDrive\Documents\NetBeansProjects\SoundTest\target

--- maven-resources-plugin:2.6:resources (default-resources) @ SoundTest ---
Using 'UTF-8' encoding to copy filtered resources.
skip non existing resourceDirectory C:\Users\montk\OneDrive\Documents\NetBeansProjects\SoundTest\src\main\resources

--- maven-compiler-plugin:3.1:compile (default-compile) @ SoundTest ---
Changes detected - recompiling the module!
Compiling 1 source file to C:\Users\montk\OneDrive\Documents\NetBeansProjects\SoundTest\target\classes

--- maven-resources-plugin:2.6:testResources (default-testResources) @ SoundTest ---
Using 'UTF-8' encoding to copy filtered resources.
skip non existing resourceDirectory C:\Users\montk\OneDrive\Documents\NetBeansProjects\SoundTest\src\test\resources

--- maven-compiler-plugin:3.1:testCompile (default-testCompile) @ SoundTest ---
No sources to compile

--- maven-surefire-plugin:2.12.4:test (default-test) @ SoundTest ---
No tests to run.

--- maven-jar-plugin:2.4:jar (default-jar) @ SoundTest ---
Building jar: C:\Users\montk\OneDrive\Documents\NetBeansProjects\SoundTest\target\SoundTest-1.0-SNAPSHOT.jar

--- maven-install-plugin:2.4:install (default-install) @ SoundTest ---
Installing C:\Users\montk\OneDrive\Documents\NetBeansProjects\SoundTest\target\SoundTest-1.0-SNAPSHOT.jar to C:\Users\montk\.m2\repository\com\mycompany\soundtest\SoundTest\1.0-SNAPSHOT\SoundTest-1.0-SNAPSHOT.jar
Installing C:\Users\montk\OneDrive\Documents\NetBeansProjects\SoundTest\pom.xml to C:\Users\montk\.m2\repository\com\mycompany\soundtest\SoundTest\1.0-SNAPSHOT\SoundTest-1.0-SNAPSHOT.pom
------------------------------------------------------------------------
BUILD SUCCESS
------------------------------------------------------------------------
Total time:  0.864 s
Finished at: 2022-12-14T20:52:55Z
------------------------------------------------------------------------

<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">    <modelVersion>4.0.0</modelVersion>    <groupId>com.mycompany.soundtest</groupId>    <artifactId>SoundTest</artifactId>    <version>1.0-SNAPSHOT</version>    <packaging>jar</packaging>   <dependencies>       <dependency>     <groupId>org.openjfx</groupId>     <artifactId>javafx-media</artifactId>     <version>18.0.1</version>       </dependency>   </dependencies>        <properties>        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>        <maven.compiler.source>18</maven.compiler.source>        <maven.compiler.target>18</maven.compiler.target>        <exec.mainClass>com.mycompany.soundtest.SoundTest</exec.mainClass>    </properties> </project>

Yes I tried to add to add it to the source file.  I am using an IDE called Apache Netbeans. When I started the project I selected an option called Java with Maven.

To add the other JavaFX libraries I simply wrote 'import javafx.scene.media.Media;'

I tried to add the code,  I got an error message:

class, interface, enum  or record expected