public void setKey(String key) {
        this.key = key;
    }
<p>
The value of <code>Key</code> depends on the operation that you want to perform:
</p>
<ul>
<li>
<p>
<b>Add a tag to a health check or hosted zone</b>: <code>Key</code> is the name that you want to give the new
tag.
</p>
</li>
<li>
<p>
<b>Edit a tag</b>: <code>Key</code> is the name of the tag that you want to change the <code>Value</code> for.
</p>
</li>
<li>
<p>
<b> Delete a key</b>: <code>Key</code> is the name of the tag you want to remove.
</p>
</li>
<li>
<p>
<b>Give a name to a health check</b>: Edit the default <code>Name</code> tag. In the Amazon Route 53 console, the
list of your health checks includes a <b>Name</b> column that lets you see the name that you've given to each
health check.
</p>
</li>
</ul>

@param key
       The value of <code>Key</code> depends on the operation that you want to perform:</p>
       <ul>
       <li>
       <p>
       <b>Add a tag to a health check or hosted zone</b>: <code>Key</code> is the name that you want to give the
       new tag.
       </p>
       </li>
       <li>
       <p>
       <b>Edit a tag</b>: <code>Key</code> is the name of the tag that you want to change the <code>Value</code>
       for.
       </p>
       </li>
       <li>
       <p>
       <b> Delete a key</b>: <code>Key</code> is the name of the tag you want to remove.
       </p>
       </li>
       <li>
       <p>
       <b>Give a name to a health check</b>: Edit the default <code>Name</code> tag. In the Amazon Route 53
       console, the list of your health checks includes a <b>Name</b> column that lets you see the name that
       you've given to each health check.
       </p>
       </li>
aws-java-sdk-route53/src/main/java/com/amazonaws/services/route53/model/Tag.java