public String getProperty(String key) {
		String value = this.properties.getProperty(key);
		if (StringUtils.isNotBlank(value)) {
			return value.trim();
		}

		List<String> keys = propertiesKeyMapper.getKeys(key);
		for (String each : checkNotNull(keys, key + " should be exists")) {
			value = this.properties.getProperty(each);
			if (StringUtils.isNotBlank(value)) {
				return value.trim();
			}
		}
		return propertiesKeyMapper.getDefaultValue(key);
	}
Get the property.

@param key property key
@return property value
ngrinder-core/src/main/java/org/ngrinder/common/util/PropertiesWrapper.java