public com.google.protobuf.ByteString getFilterBytes() {
      java.lang.Object ref = filter_;
      if (ref instanceof String) {
        com.google.protobuf.ByteString b =
            com.google.protobuf.ByteString.copyFromUtf8((java.lang.String) ref);
        filter_ = b;
        return b;
      } else {
        return (com.google.protobuf.ByteString) ref;
      }
    }
<pre>
A filter expression that matches resources returned in the response.
The expression must specify the field name, a comparison
operator, and the value that you want to use for filtering. The value
must be a string, a number, or a boolean. The comparison operator
must be `=`, `!=`, `&gt;`, or `&lt;`.

For example, if you are filtering a list of IP addresses, you can
exclude the ones named `example-ip` by specifying
`name != "example-ip"`.

To filter on multiple expressions, provide each separate expression within
parentheses. For example:
```
(name = "example-ip")
(createTime &gt; "2021-04-12T08:15:10.40Z")
```

By default, each expression is an `AND` expression. However, you
can include `AND` and `OR` expressions explicitly.
For example:
```
(name = "example-ip-1") AND
(createTime &gt; "2021-04-12T08:15:10.40Z") OR
(name = "example-ip-2")
```
</pre>

<code>string filter = 4;</code>

@return The bytes for filter.
java-vmwareengine/proto-google-cloud-vmwareengine-v1/src/main/java/com/google/cloud/vmwareengine/v1/ListExternalAddressesRequest.java