When we write character to file and then read it back from file using supported ISO2022JP encoding we get different chars, e.g
"Written char: ''(code: 15), read char: '!)'(code: 65533)"

Below is a small java class that demonstrates the problem:

import java.io.*;

public class ISO2022JP_Test {
    public static final int TOP_VALUE = 10000;
    public static int wrongCounter = 0;
    
    public static void main(String[] args) {
        System.out.println("Encoding being used: " + System.getProperty("file.encoding"));
        char[] chars = new char[TOP_VALUE];
        for (int i = 0; i < TOP_VALUE; i++) {
            testFileWriteRead((char)i);
        }
        System.out.println(wrongCounter + " characters don't match of " + TOP_VALUE);
    }

    private static void testFileWriteRead(char writeChar) {
        try {
            File tmp = File.createTempFile("read_write", "test");
            FileWriter fw = new FileWriter(tmp);
            fw.write(writeChar);
            fw.close();
            FileReader fr = new FileReader(tmp);
            char readChar = (char)fr.read();
            if (readChar != writeChar) {
                System.out.println("Written char: '" + writeChar + "'(code: " + (int)writeChar + " ), read char: '" + readChar + "'(code: " + (int)readChar + ")");
                wrongCounter++;
            }
            fr.close();
            tmp.delete();
        } catch (IOException ex) {
            ex.printStackTrace(System.out);
        }
        
    }
}

If we run this program with option "-Dfile.encoding=ISO2022JP" we get big list of unmatching characters with following summary: 9641 characters don't match of 10000