private static Entry<String, String> parsePropertyLine(String propertyLine, int lineNumber) {
        String[] pair = propertyLine.split("=", 2);
        if (pair.length != 2) {
            throw new IllegalArgumentException("Invalid property format: no '=' character is found on line " + lineNumber);
        }

        String propertyKey   = pair[0].trim();
        String propertyValue = pair[1].trim();

        return new AbstractMap.SimpleImmutableEntry<String, String>(propertyKey, propertyValue);
    }
Returns the profile name if this line indicates the beginning of a new
profile section. Otherwise, returns null.
aws-java-sdk-core/src/main/java/com/amazonaws/auth/profile/internal/AbstractProfilesConfigFileScanner.java