Why were Nativists in favor of the Chinese Exclusion Act?

Meant to curb the influx of Chinese immigrants to the United States, particularly California, The Chinese Exclusion Act of 1882 suspended Chinese immigration for ten years and declared Chinese immigrants ineligible for naturalization. President Chester A. Arthur signed it into law on May 6, 1882. Chinese-Americans already in the country challenged the constitutionality of the discriminatory acts, but their efforts failed.