cas/src/main/java/org/springframework/security/cas/authentication/CasAuthenticationProvider.java
public void afterPropertiesSet() throws Exception {
		Assert.notNull(this.authenticationUserDetailsService,
				"An authenticationUserDetailsService must be set");
		Assert.notNull(this.ticketValidator, "A ticketValidator must be set");
		Assert.notNull(this.statelessTicketCache, "A statelessTicketCache must be set");
		Assert.hasText(
				this.key,
				"A Key is required so CasAuthenticationProvider can identify tokens it previously authenticated");
		Assert.notNull(this.messages, "A message source must be set");
	}
public void afterPropertiesSet() throws Exception {
		Assert.notNull(this.authenticationUserDetailsService,
				"An authenticationUserDetailsService must be set");
		Assert.notNull(this.ticketValidator, "A ticketValidator must be set");
		Assert.notNull(this.statelessTicketCache, "A statelessTicketCache must be set");
		Assert.hasText(
				this.key,
				"A Key is required so CasAuthenticationProvider can identify tokens it previously authenticated");
		Assert.notNull(this.messages, "A message source must be set");
	}
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