protected boolean trusted(String requestedType) {
		if (requestedType.equals(NonTrustedHeaderType.class.getName())) {
			return true;
		}
		if (!this.trustedPackages.isEmpty()) {
			int lastDot = requestedType.lastIndexOf('.');
			if (lastDot < 0) {
				return false;
			}
			String packageName = requestedType.substring(0, lastDot);
			for (String trustedPackage : this.trustedPackages) {
				if (packageName.equals(trustedPackage)
						|| packageName.startsWith(trustedPackage + ".")) {
					return true;
				}
			}
			return false;
		}
		return true;
	}
Add packages to the trusted packages list (default {@code java.util, java.lang})
used when constructing objects from JSON. If any of the supplied packages is
{@code "*"}, all packages are trusted. If a class for a non-trusted package is
encountered, the header is returned to the application with value of type
{@link NonTrustedHeaderType}.
@param packagesToTrust the packages to trust.
spring-cloud-alibaba-starters/spring-cloud-starter-stream-rocketmq/src/main/java/com/alibaba/cloud/stream/binder/rocketmq/support/JacksonRocketMQHeaderMapper.java