public java.util.List<String> getAllowedInstanceTypes() {
        if (allowedInstanceTypes == null) {
            allowedInstanceTypes = new com.amazonaws.internal.SdkInternalList<String>();
        }
        return allowedInstanceTypes;
    }
<p>
The instance types to apply your specified attributes against. All other instance types are ignored, even if they
match your specified attributes.
</p>
<p>
You can use strings with one or more wild cards, represented by an asterisk (<code>*</code>), to allow an
instance type, size, or generation. The following are examples: <code>m5.8xlarge</code>, <code>c5*.*</code>,
<code>m5a.*</code>, <code>r*</code>, <code>*3*</code>.
</p>
<p>
For example, if you specify <code>c5*</code>,Amazon EC2 will allow the entire C5 instance family, which includes
all C5a and C5n instance types. If you specify <code>m5a.*</code>, Amazon EC2 will allow all the M5a instance
types, but not the M5n instance types.
</p>
<note>
<p>
If you specify <code>AllowedInstanceTypes</code>, you can't specify <code>ExcludedInstanceTypes</code>.
</p>
</note>
<p>
Default: All instance types
</p>

@return The instance types to apply your specified attributes against. All other instance types are ignored, even
        if they match your specified attributes.</p>
        <p>
        You can use strings with one or more wild cards, represented by an asterisk (<code>*</code>), to allow an
        instance type, size, or generation. The following are examples: <code>m5.8xlarge</code>,
        <code>c5*.*</code>, <code>m5a.*</code>, <code>r*</code>, <code>*3*</code>.
        </p>
        <p>
        For example, if you specify <code>c5*</code>,Amazon EC2 will allow the entire C5 instance family, which
        includes all C5a and C5n instance types. If you specify <code>m5a.*</code>, Amazon EC2 will allow all the
        M5a instance types, but not the M5n instance types.
        </p>
        <note>
        <p>
        If you specify <code>AllowedInstanceTypes</code>, you can't specify <code>ExcludedInstanceTypes</code>.
        </p>
        </note>
        <p>
        Default: All instance types
aws-java-sdk-ec2/src/main/java/com/amazonaws/services/ec2/model/InstanceRequirementsRequest.java