core/src/main/java/org/springframework/security/access/intercept/NullRunAsManager.java
public Authentication buildRunAs(Authentication authentication, Object object,
			Collection<ConfigAttribute> config) {
		return null;
	}
public Authentication buildRunAs(Authentication authentication, Object object,
			Collection<ConfigAttribute> config) {
		return null;
	}
public Authentication buildRunAs ( Authentication authentication , Object object , Collection < ConfigAttribute > config ) { return null ; }
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