java在HTML文件中引用servlet。Tomcat中的war文件

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我创建了一个索引。我在tomcat上部署的Java（.war）应用程序的html文件

我已经有了一个Java Servlet文件，可以在远程数据库服务器上查询我存储在那里的图片

java servlet文件称为ImageServlet。爪哇

我需要HTML页面来显示ImageServlet显示的图像。java查询

我只是不知道如何在servlet检索我的图片时引用它

下面是ImageServlet文件：

package test;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.sql.Blob;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.bind.DatatypeConverter;

public class ImageServlet extends HttpServlet
{
  Connection con = null;

  public Connection getConnection()
  {
    try {
      Class.forName("com.mysql.jdbc.Driver");
      String url = System.getenv("FUJI_MYSQL_URL");
      return DriverManager.getConnection(url,             
System.getenv("FUJI_MYSQL_USER"), System.getenv("FUJI_MYSQL_PASS"));
    }
    catch (Exception ex)
    {
      System.out.println(ex.getMessage());
    }return null;
  }

  public static byte[] getImageById(Connection con)
  {
    String query = "select photo from photos where picid = 1";
    try
    {
      PreparedStatement stmt = con.prepareStatement(query);

      stmt.execute();
      ResultSet resultSet = stmt.getResultSet();
      resultSet.first();
      Blob blob = resultSet.getBlob(1);
      stmt.close();
      con.close();
      return blob.getBytes(1L, (int)blob.length());
    } catch (Exception ex) {
      System.out.println(ex.getMessage());
    }return null;
  }

  public void doGet(HttpServletRequest req, HttpServletResponse res)
    throws ServletException, IOException
  {
    PrintWriter out = res.getWriter();

    Connection con = null;
    con = getConnection();
    byte[] data = getImageById(con);

    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    baos.write(data);

    out.println("<!DOCTYPE html><html xmlns=\"http://www.w3.org/1999/xhtml\"><head><title>PI_SQLogo.png</title></head><body><img src='data:image/png;base64," + DatatypeConverter.printBase64Binary(baos.toByteArray()) + "'></body></html>");
    out.close();
  }
}

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