spring-session-core/src/main/java/org/springframework/session/web/http/DefaultCookieSerializer.java
private String base64Encode(String value) {
		byte[] encodedCookieBytes = Base64.getEncoder().encode(value.getBytes());
		return new String(encodedCookieBytes);
	}
private String base64Encode(String value) {
		byte[] encodedCookieBytes = Base64.getEncoder().encode(value.getBytes());
		return new String(encodedCookieBytes);
	}
Encode the value using Base64.
@param value the String to Base64 encode
@return the Base64 encoded value
@since 1.2.2