Apply Singleton pattern to EuRxManager

[phj0407]

As - Is

While I apply Euphony library for sample app project, I find using one more object can cause malfunciton. I think applying singleton pattern to EuRxManager can prevent potential issue.

To-Do

Now, EuRxManager have 3 constructor.

public EuRxManager() {
		mOption = EuOption.builder()
				.modeWith(EuOption.ModeType.DEFAULT)
				.encodingWith(EuOption.CodingType.BASE16)
				.modulationWith(EuOption.ModulationType.FSK)
				.build();
	}

	public EuRxManager(RxEngineType engineType) {
		rxEngineType = engineType;
		if(rxEngineType == RxEngineType.EUPHONY_NATIVE_ENGINE)
			nativeCore = EuNativeConnector.getInstance();
		else
			nativeCore = null;
	}

	public EuRxManager(EuOption.ModeType mode) {
		mOption = EuOption.builder()
				.modeWith(mode)
				.build();
	}

I think public EuRxManager(),public EuRxManager(EuOption.ModeType mode) can be combined. And initializing nativeCore can be solved seperately by add new method.

[designe]

@phj0407 Great Idea! 👍
Actually, There are 3 important things about Singleton

1. It is only 1 instance.
2. it is created once!
3. no argument with creation function. because above two.

Please show me your code! 👍

[phj0407]

Hello, while I apply 'Singleton' to code with your advice, I have question about constructor. I saw existing constructor initialized mOption and class has function for initialize mOption - setOption (EuOption mOption). Also, nativeCore is created depending on rxEngineType.

// Existing code
public EuRxManager() {
		mOption = EuOption.builder()
				.modeWith(EuOption.ModeType.DEFAULT)
				.encodingWith(EuOption.CodingType.BASE16)
				.modulationWith(EuOption.ModulationType.FSK)
				.build();
	}

public EuRxManager(RxEngineType engineType) {
		rxEngineType = engineType;
		if(rxEngineType == RxEngineType.EUPHONY_NATIVE_ENGINE)
			nativeCore = EuNativeConnector.getInstance();
		else
			nativeCore = null;
	}

public void setOption(EuOption mOption) {
		this.mOption = mOption;
	}

public void setRxEngineType(RxEngineType type) {
		this.rxEngineType = type;
	}

So I'm curious that if I apply 'Singleton' ,

• do I have initialize default mOption like below code?
• Is it okay to change 'setRxEngineType' ?

private EuOption mOption =  EuOption.builder()
				.modeWith(EuOption.ModeType.DEFAULT)
				.encodingWith(EuOption.CodingType.BASE16)
				.modulationWith(EuOption.ModulationType.FSK)
				.build();

private static class InnerInstanceClazz{
		private static final EuRxManager instance = new EuRxManager();
	}

public static EuRxManager getInstance(){
		return InnerInstanceClazz.instance;
	}

public void setRxEngineType(RxEngineType type) {
		this.rxEngineType = type;
		if(this.rxEngineType == RxEngineType.EUPHONY_NATIVE_ENGINE)
			nativeCore = EuNativeConnector.getInstance();
		else
			nativeCore = null;
	}

[designe]

@phj0407 You're right :)
actually, signleton shouldn't have paramaters.
because, initialized once and re-use a bunch of times.

We need to make a setter function for RxEngineType like you suggested.

Looks good to me :)