private void ensureBlocksIsMutable() {
      if (!((bitField0_ & 0x00000008) != 0)) {
        blocks_ = new java.util.ArrayList<com.google.cloud.vision.v1p2beta1.Block>(blocks_);
        bitField0_ |= 0x00000008;
      }
    }
<pre>
Page height. For PDFs the unit is points. For images (including
TIFFs) the unit is pixels.
</pre>

<code>int32 height = 3;</code>

@return This builder for chaining.
java-vision/proto-google-cloud-vision-v1p2beta1/src/main/java/com/google/cloud/vision/v1p2beta1/Page.java