private static float[] initialCompressionRatio() {
        float[] compressionRatio = new float[CompressionType.values().length];
        for (CompressionType type : CompressionType.values()) {
            compressionRatio[type.id] = type.rate;
        }
        return compressionRatio;
    }
Set the compression estimation for a topic compression type combination. This method is for unit test purpose.
clients/src/main/java/org/apache/kafka/common/record/CompressionRatioEstimator.java