Unsupported major.minor version 52.0
Pictures:
Command Prompt showing versions
Picture of error
Hello.java
import java.applet.Applet;
import java.awt.*;
public class Hello extends Applet {
// Java applet to draw "Hello World"
public void paint (Graphics page) {
page.drawString ("Hello World!", 50, 50);
}
}
Hello.html
<HTML>
<HEAD>
<TITLE>HelloWorld Applet</TITLE>
</HEAD>
<BODY>
<APPLET CODE="Hello.class" WIDTH=300 HEIGHT=150>
</APPLET>
</BODY>
</HTML>
Error
Hello : Unsupported major.minor version 52.0
What may the problem be?
Answer
The issue is because of Java version mismatch. Referring to the Wikipedia Java Class Reference:
- Java SE 14 = 58
- Java SE 13 = 57
- Java SE 12 = 56 (0x38 hex)
- Java SE 11 = 55 (0x37 hex)
- Java SE 10 = 54
- Java SE 9 = 53
- Java SE 8 = 52
- Java SE 7 = 51
- Java SE 6.0 = 50
- Java SE 5.0 = 49
- JDK 1.4 = 48
- JDK 1.3 = 47
- JDK 1.2 = 46
- JDK 1.1 = 45
These are the assigned major numbers. The error regarding the unsupported major.minor version is because during compile time you are using a higher JDK and a lower JDK during runtime.
Thus, the 'major.minor version 52.0' error is possibly because the jar was compiled in JDK 1.8, but you are trying to run it using a JDK 1.7 environment. The reported number is the required number, not the number you are using. To solve this, it's always better to have the JDK and JRE pointed to the same version.
In IntelliJ IDEA,
- Go to Maven Settings → Maven → Importing. Set the JDK for importer to 1.8.
- Go to Maven Settings → Maven → Runner. Set the JRE to 1.8.
- Go to menu File* → Project Structure → SDKs. Make sure the JDK home path is set to 1.8.
Restart IntelliJ IDEA.
Another approach which might help is by instructing IntelliJ IDEA which JDK version to start up with.
Go to: /Applications/IntelliJ\ IDEA\ 15\ CE.app/Contents/Info.plist and replace the JVM version with:
<key>JVMVersion</key>
<string>1.8*</string>