Code example for Set

Methods: contains

0
		String value = source.trim();
		if ("".equals(value)) {
			return null; 
		} 
		value = value.toLowerCase();
		if (trueValues.contains(value)) {
			return Boolean.TRUE;
		} 
		else if (falseValues.contains(value)) {
			return Boolean.FALSE;
		} 
		else { 
			throw new IllegalArgumentException("Invalid boolean value '" + source + "'");
		} 
	} 
 
} 
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