web/src/main/java/org/springframework/security/web/authentication/LoginUrlAuthenticationEntryPoint.java
public void afterPropertiesSet() throws Exception {
		Assert.isTrue(
				StringUtils.hasText(loginFormUrl)
						&& UrlUtils.isValidRedirectUrl(loginFormUrl),
				"loginFormUrl must be specified and must be a valid redirect URL");
		if (useForward && UrlUtils.isAbsoluteUrl(loginFormUrl)) {
			throw new IllegalArgumentException(
					"useForward must be false if using an absolute loginFormURL");
		}
		Assert.notNull(portMapper, "portMapper must be specified");
		Assert.notNull(portResolver, "portResolver must be specified");
	}
public void afterPropertiesSet() throws Exception {
		Assert.isTrue(
				StringUtils.hasText(loginFormUrl)
						&& UrlUtils.isValidRedirectUrl(loginFormUrl),
				"loginFormUrl must be specified and must be a valid redirect URL");
		if (useForward && UrlUtils.isAbsoluteUrl(loginFormUrl)) {
			throw new IllegalArgumentException(
					"useForward must be false if using an absolute loginFormURL");
		}
		Assert.notNull(portMapper, "portMapper must be specified");
		Assert.notNull(portResolver, "portResolver must be specified");
	}
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