In Optical Network-on-Chip (ONoC), both routing and wavelength assignment (RWA) have an impact on the Optical Signal-to-Noise Ratio (OSNR), which further influence the power efficiency and scalability. In the state-of-the-art, the consideration of routing is separate with the wavelength assignment, which could not reach a holistic optimization. Also, there is a need of trade-off among multidimensional performance factors in the design of RWA. In this article, we propose a Multidimensional Integrated Predictive RWA (named as MIP-RWA), based on the Fuzzy Logic System (FLS). The MIP-RWA considers routing and wavelength assignment holistically, taking into consideration of multidimensional performance factors at the same time. The predictive scheme is proposed to work with RWA and further reduce the delay in RWA. The evaluation shows that the proposed MIP-RWA can obtain better trade-off of the performance factors. The traffic prediction accuracy of the Fuzzy Neural Network (FNN) improves by 5.29%, 4.79%, and 6.2% respectively under the uniform, transpose, and hotspot traffic, compared with the Long Short-Term Memory (LSTM)-based. Thanks to the traffic predictive scheme, the proposed MIP-RWA reduces the end-to-end delay (ete delay) by 17.77%, 17.39%, and 16.66% respectively under uniform, transpose, and hotspot traffic, compared with the methods without predictive scheme. Also, compared with current RWA methods, the proposed MIP-RWA improves 11.21 dB in OSNR and 21.47% in delay in average.