Various optimizations for nullity checks

[Katsute]

Mal4J/src/main/java/dev/katsute/mal4j/Json.java

Lines 276 to 299 in bf3dcd6

	public final int getInt(final String key){
	final Object value = map.get(key);
	return value instanceof String ? Integer.parseInt((String) value) : ((Number) value).intValue();
	}
	public final double getDouble(final String key){
	final Object value = map.get(key);
	return value instanceof String ? Double.parseDouble((String) value) : ((Number) value).doubleValue();
	}
	public final float getFloat(final String key){
	final Object value = map.get(key);
	return value instanceof String ? Float.parseFloat((String) value) : ((Number) value).floatValue();
	}
	public final long getLong(final String key){
	final Object value = map.get(key);
	return value instanceof String ? Long.parseLong((String) value) : ((Number) value).longValue();
	}
	public final boolean getBoolean(final String key){
	final Object value = map.get(key);
	return value instanceof String ? Boolean.parseBoolean((String) value) : (boolean) value;
	}

Return null instead of throwing a NPE.

Use .valueOf rather than .parse, try catch on NFE.

Mal4J/src/main/java/dev/katsute/mal4j/Json.java

Lines 301 to 303 in bf3dcd6

	public final JsonObject getJsonObject(final String key){
	return (JsonObject) map.get(key);
	}

Return an empty JsonObject if null, this will protect against chained nulls.

Mal4J/src/main/java/dev/katsute/mal4j/Json.java

Lines 313 to 319 in bf3dcd6

	public final JsonObject[] getJsonArray(final String key){
	final List<?> list = (List<?>) map.get(key);
	final List<JsonObject> arr = new ArrayList<>();
	for(final Object o : list)
	arr.add((JsonObject) o);
	return arr.toArray(new JsonObject[0]);
	}

Return an empty array if null, this will protect against null loops.

Various as methods need to be rewritten to return null if null object.

These changes should remove the need for requireNonNull.