[Crash] Playing an invalid song will crash the game

[5lx]

When I tried to listen an invalid song (m4a format), the log will show:

[Client thread/INFO]: javax.sound.sampled.UnsupportedAudioFileException: file is not a supported file type

Then if I try to click any button on the Radio GUI, It won't work any more and the log will say something about the codec:

io.netty.handler.codec.EncoderException: java.lang.NullPointerException
    at io.netty.handler.codec.MessageToMessageEncoder.write(MessageToMessageEncoder.java:107)
    at io.netty.handler.codec.MessageToMessageCodec.write(MessageToMessageCodec.java:116) 

Then if I close the GUI, and reopen it, it will crash the game:

java.lang.NullPointerException
    at pcl.OpenFM.GUI.GuiRadio.func_73866_w_(GuiRadio.java:84) ~[GuiRadio.class:?]
    at net.minecraft.client.gui.GuiScreen.func_146280_a(GuiScreen.java:255) ~[bdw.class:?]
    at net.minecraft.client.gui.inventory.GuiContainer.func_146280_a(GuiContainer.java) ~[bex.class:?]

OpenFM version: OpenFM-1.7.10-0.1.0-34 Forge version: 1.7.10-10.13.4.1614 OC version: OpenComputers-MC1.7.10-1.5.22.46-universal

[5lx]

In pcl/OpenFM/GUI/GuiRadio.java

if (!(this.radio.streamURL == null) || !this.radio.streamURL.equals("")) {
    this.streamTextBox.setText(this.radio.streamURL);
} else {
    this.streamTextBox.setText(OFMConfiguration.defaultURL);
}

The problem is the code determine !(this.radio.streamURL == null) and !this.radio.streamURL.equals("") in the same time.

[CaitlynMainer]

This is short-circuiting

One great example of short-circuiting relates to object references:

if (a != null && a.getFoo() != 42) {
    // Do something
}
a.getFoo() would normally throw a NullPointerException if a were null, but because the expression short-circuits, if a != null is false, the a.getFoo() part never happens, so we don't get an exception.

Note that not all expressions are short-cicuited. The || and && operators are short-circuited, but | and & are not, nor are * or /; in fact most operators are not.

The issue is not that they are "on the same line" But that I used Logical OR, not Logical AND (I have ||, not &&). The check needs to be if streamURL is not null AND streamURL is not empty then set the textBox, Currently it checks if its not null OR it's not empty.

[CaitlynMainer]

Build 35 will be on curse as soon as it is approved if you could test this change for me it would be great.

[5lx]

@CaitlynMainer Thanks for the fixing, it won't crash any more.

But I found another small issue. After playing an invalid song, the Radio can't play new songs, even if I corrected the url. There's no response when I click the play button, and the logs didn't show anything. In this situation, if I try to use .play() function, the logs will show it is streaming, but I can't hear the song.

PS: After playing an invalid song, the .isPlaying will return true. I don't know if this is the reason.

[CaitlynMainer]

Yeah that's been an issue since the beginning, basically the backend decoder fully crashes, and there isn't a decent way I've found the respawn it.

[5lx]

Maybe now the best way is to destroy and place it on again. Thanks for your detailed explanation.