content: package com.taobao.arthas.grpcweb.proxy.server;
  
  import com.taobao.arthas.grpcweb.proxy.MessageUtils;
  import org.junit.Assert;
  import org.junit.Test;
  
  public class MessageUtilsTest {
  
      @Test
      public void testValidateContentType(){
          String contentType1 = "application/grpc-web";
          MessageUtils.ContentType result1 = MessageUtils.validateContentType(contentType1);
          String contentType2 = "application/grpc-web+proto";
          MessageUtils.ContentType result2 = MessageUtils.validateContentType(contentType2);
          String contentType3 = "application/grpc-web-text";
          MessageUtils.ContentType result3 = MessageUtils.validateContentType(contentType3);
          String contentType4 = "application/grpc-web-text+proto";
          MessageUtils.ContentType result4 = MessageUtils.validateContentType(contentType4);
          MessageUtils.ContentType result5 = MessageUtils.ContentType.GRPC_WEB_BINARY;
          try {
              String contentType5 = null;
              result5 = MessageUtils.validateContentType(contentType5);
          }catch (IllegalArgumentException e){
              result5 = null;
          }
  
          Assert.assertEquals(result1,MessageUtils.ContentType.GRPC_WEB_BINARY);
          Assert.assertEquals(result2,MessageUtils.ContentType.GRPC_WEB_BINARY);
          Assert.assertEquals(result3,MessageUtils.ContentType.GRPC_WEB_TEXT);
          Assert.assertEquals(result4,MessageUtils.ContentType.GRPC_WEB_TEXT);
          Assert.assertNull(result5);
      }
  }
  