Why can't I access the ImageTypes??

Question about the task

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I keep getting this error..... com/codegym/task/task16/task1631/ImageReaderFactory.java:7: error: cannot find symbol public static ImageReader getImageReader(ImageTypes type) throws Exception { ^ symbol: class ImageTypes location: class com.codegym.task.task16.task1631.ImageReaderFactory Thanks

1. Take a careful look at the classes you have.
2. In separate files in the common package, create JpgReader, PngReader, and BmpReader classes that implement the ImageReader interface.
3. In a separate file in the main package, create the ImageReaderFactory class with one method.
3.1. Think about what it should be called.
3.2. Think about which modifiers this method should have.
4. This method should:
4.1. For each value in ImageTypes, return the appropriate Reader. For example, for
ImageTypes.JPG, return a JpgReader;
4.2. If an invalid argument is passed, then throw an exception:
IllegalArgumentException("Unknown image type").

Requirements:

Create a JpgReader class in the common package. It must implement the ImageReader interface.
Create a PngReader class in the common package. It must implement the ImageReader interface.
Create a BmpReader class in the common package. It must implement the ImageReader interface.
Create a public class named ImageReaderFactory.
Add a public static method getImageReader with an ImageTypes parameter to the ImageReaderFactory class.
The getImageReader method must create and return a suitable Reader.
The getImageReader method must throw an IllegalArgumentException if an invalid argument is passed.

package com.codegym.task.task16.task1631; // import com.codegym.task.task16.task1631.common.ImageReader; // import com.codegym.task.task16.task1631.common.ImageTypes; public class Solution { public static void main(String[] args) { ImageReader reader = ImageReaderFactory.getImageReader(ImageTypes.JPG); } }

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Gellert Varga

Level 23 , Szekesfehervar, Hungary

26 August 2021, 10:09

1) If you want to use classes from another package, you need to import them at the beginning of the file. You may be familiar from previous examples with this next line at the very beginning of the program:

import java.util.*; // the asterisk means: all from the 'util'.

Now in this task, the class structure was such that we have a separate package. It is called "common". If you look at the task on the CG web page, clicking on the "Class tree" button on the left will show you the class structure, but of course you can also look at this in IntelliJ. This "common" package contains the ImageReader for which you got the "can't find symbol" message. That's because you commented out the two codelines (in Solution.java) which would import that package. 2) After correcting all these, two more errors were reported to me by the JVM: - In the ImageReaderFactory, in the switch structure: 'break' is inaccessible. You can't write any other command after the return command, because it is inaccessible to the JVM. With return, you exit that block. This return command should be the last command in non void methods too. - Since the main() method calls a method that can throw an exception back to the caller, main() should also be able to throw the exception.