ldap/src/main/java/org/springframework/security/ldap/LdapUtils.java
public static void closeContext(Context ctx) {
		if (ctx instanceof DirContextAdapter) {
			return;
		}

		try {
			if (ctx != null) {
				ctx.close();
			}
		}
		catch (NamingException e) {
			logger.error("Failed to close context.", e);
		}
	}
public static void closeContext(Context ctx) {
		if (ctx instanceof DirContextAdapter) {
			return;
		}

		try {
			if (ctx != null) {
				ctx.close();
			}
		}
		catch (NamingException e) {
			logger.error("Failed to close context.", e);
		}
	}
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