web/src/main/java/org/springframework/security/web/header/writers/HpkpHeaderWriter.java
public void setPins(Map<String, String> pins) {
		Assert.notNull(pins, "pins cannot be null");
		this.pins = pins;
		updateHpkpHeaderValue();
	}
public void setPins(Map<String, String> pins) {
		Assert.notNull(pins, "pins cannot be null");
		this.pins = pins;
		updateHpkpHeaderValue();
	}
<p>
Sets the value for the pin- directive of the Public-Key-Pins header.
</p>

<p>
The pin directive specifies a way for web host operators to indicate
a cryptographic identity that should be bound to a given web host.
See <a href="https://tools.ietf.org/html/rfc7469#section-2.1.1">Section 2.1.1</a> for additional details.
</p>

<p>
To get a pin of

Public-Key-Pins:
pin-sha256="d6qzRu9zOECb90Uez27xWltNsj0e1Md7GkYYkVoZWmM=";
pin-sha256="E9CZ9INDbd+2eRQozYqqbQ2yXLVKB9+xcprMF+44U1g="

Use

<code>
Map&lt;String, String&gt; pins = new HashMap&lt;String, String&gt;();
pins.put("d6qzRu9zOECb90Uez27xWltNsj0e1Md7GkYYkVoZWmM=", "sha256");
pins.put("E9CZ9INDbd+2eRQozYqqbQ2yXLVKB9+xcprMF+44U1g=", "sha256");
</code>
</p>

@param pins the map of base64-encoded SPKI fingerprint &amp; cryptographic hash algorithm pairs.
@throws IllegalArgumentException if pins is null