打开下载api里面的init.js文件，我的目录是：D:\GreenProgram\apache-tomcat-8.5.32\webapps\arcgis_js_api\library\4.8\init.js，把[HOSTNAME_AND_PATH_TO_JSAPI]替换成api在本地机器上的部署路径，注意路径无需包含。我的配置如下：127.0.0.1:8080/arcgis_js_api/library/4.8/dojo
2>.配置dojo.js文件
打开下载api里面的dojo文件夹里面的dojo.js，我的目录是：D:\GreenProgram\apache-tomcat-8.5.32\webapps\arcgis_js_api\library\4.8\dojo\dojo.js，把[HOSTNAME_AND_PATH_TO_JSAPI]替换成api在本地机器上的部署路径，注意路径无需包含。我的配置如下：127.0.0.1:8080/arcgis_js_api/library/4.8/dojo
PS：这里要注意一点，最新的4.8默认的baseUrl都是https打头的，如果只按照上述配置你打开测试页面肯定会报错的，所以上述两个地方我都改成了http打头，另外在arcgis_js_api\library\downloads文件夹里有esri的简单安装教程，里面Requirements节中有说到这个，这里我说下怎么在tomcate中进行MIME类型注册。
Tomcat在返回静态资源时，会根据资源文件的扩展名产生对应的content-type头（也即MIME类型）添加到response header中。在Tomcat的conf\web.xml规定了扩展名及相应MIME的映射（占了web.xml 87%的篇幅），如下：【注意我仅列出了我添加的那部分】
<!-- ===================== Default MIME Type Mappings =================== --> <!-- When serving static resources, Tomcat will automatically generate --> <!-- a "Content-Type" header based on the resource's filename extension, --> <!-- based on these mappings. Additional mappings can be added here (to --> <!-- apply to all web applications), or in your own application's web.xml --> <!-- deployment descriptor. --> <!-- Note: Extensions are always matched in a case-insensitive manner. --> <mime-mapping> <extension>.ttf</extension> <mime-type>application/octet-stream</mime-type> </mime-mapping> <mime-mapping> <extension>.wasm</extension> <mime-type>application/wasm</mime-type> </mime-mapping> <mime-mapping> <extension>.woff</extension> <mime-type>application/font-woff</mime-type> </mime-mapping> <mime-mapping> <extension>.woff2</extension> <mime-type>application/font-woff2</mime-type> </mime-mapping> <mime-mapping> <extension>.wsv</extension> <mime-type>application/octet-stream</mime-type> </mime-mapping> <mime-mapping>