在web.xml上映射Servlet

Question

当我开始收到404错误时，我正在对web.xml进行一些更改。我的servlet只是打印json数据。或者我的tomcat服务器在我尝试运行代码时没有响应。问题出在哪里？我尝试过不同的servlet映射，但似乎仍然无法工作。感谢您花时间审阅我的代码，非常感谢！

    <servlet>
        <servlet-name>inventory</servlet-name>
        <servlet-class>InventoryServlet</servlet-class> 
    </servlet>
    <servlet-mapping>
    <servlet-name>inventory</servlet-name>
    <url-pattern>InventoryServlet</url-pattern>
    </servlet-mapping>
</web-app>

servlet的开始，它只是打印出JSON数据。

   @SuppressWarnings("serial")
    public class InventoryServlet extends HttpServlet {
        @Override
        protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
            ArrayList < LavaLamp > lamps = new ArrayList < LavaLamp > ();
        Manufacturer lavaLampDotCom = new Manufacturer();
        lavaLampDotCom.setManName("lavalamp.com");
        LavaLamp blulava = new LavaLamp();
        blulava.setLavaName("Blulava");
        blulava.setType("Original");
        blulava.setPrice(17.99);
        blulava.setHeight(12);
        blulava.setWidth(3.5);
        blulava.setWaxColor("Blue");
        blulava.setLiquidColor("Red");
        blulava.setId(1);
        blulava.setCostBook(new SimpleCostBook(blulava.getPrice()));
        blulava.setManufacturer(lavaLampDotCom);
        blulava.setManId(1);
        blulava.setSku(1111);
        lamps.add(blulava);
        Manufacturer volcanicLavaDotNet = new Manufacturer();
        volcanicLavaDotNet.setManName("volcaniclava.net");
        LavaLamp bloodlava = new LavaLamp();
        bloodlava.setLavaName("Blood Lava");
        bloodlava.setType("Original");
        bloodlava.setWaxColor("Red");
        bloodlava.setLiquidColor("Green");
        bloodlava.setPrice(15.99);
        bloodlava.setHeight(12);
        bloodlava.setWidth(3.5);
        bloodlava.setId(2);
        bloodlava.setCostBook(new SimpleCostBook(bloodlava.getPrice()));
        bloodlava.setManufacturer(volcanicLavaDotNet);
        bloodlava.setManId(4);
        bloodlava.setSku(2222);
        lamps.add(bloodlava);

        Manufacturer lavaHouseDotCom = new Manufacturer();
        lavaHouseDotCom.setManName("lavahouse.com");
        LavaLamp purppower = new LavaLamp();
        purppower.setLavaName("Purp Power");
        purppower.setType("Large");
        purppower.setWaxColor("Purple");
        purppower.setLiquidColor("Yellow");
        purppower.setPrice(22.99);
        purppower.setHeight(16);
        purppower.setWidth(4.5);
        purppower.setId(3);
        purppower.setCostBook(new SimpleCostBook(purppower.getPrice()));
        purppower.setManufacturer(lavaHouseDotCom);
        purppower.setManId(3);
        purppower.setSku(3333);
        lamps.add(purppower);
        Manufacturer lavaCountryDotOrg = new Manufacturer();
        lavaCountryDotOrg.setManName("lavacountry.org");
        LavaLamp mellowyellow = new LavaLamp();
        mellowyellow.setLavaName("Mellow Yellow");
        mellowyellow.setType("Large");
        mellowyellow.setWaxColor("Yellow");
        mellowyellow.setLiquidColor("Black");
        mellowyellow.setPrice(29.99);
        mellowyellow.setHeight(16);
        mellowyellow.setWidth(4.5);
        mellowyellow.setId(4);
        mellowyellow.setCostBook(new SimpleCostBook(mellowyellow.getPrice()));
        mellowyellow.setManufacturer(lavaCountryDotOrg);
        mellowyellow.setManId(5);
        mellowyellow.setSku(4444);
        lamps.add(mellowyellow);
        Manufacturer jamiesBasementDotSwag = new Manufacturer();
        jamiesBasementDotSwag.setManName("jamiesbasement.swag");
        LavaLamp rainbowmadness = new LavaLamp();
        rainbowmadness.setLavaName("Rainbow Madness");
        rainbowmadness.setType("XXL");
        rainbowmadness.setWaxColor("Rainbow");
        rainbowmadness.setLiquidColor("Clear");
        rainbowmadness.setPrice(49.99);
        rainbowmadness.setHeight(50);
        rainbowmadness.setWidth(12.5);
        rainbowmadness.setId(5);
        rainbowmadness.setCostBook(new SimpleCostBook(rainbowmadness.getPrice()));
        rainbowmadness.setManufacturer(jamiesBasementDotSwag);
        rainbowmadness.setManId(2);
        rainbowmadness.setSku(5555);
        lamps.add(rainbowmadness);
        Manufacturer lavaLampCom = new Manufacturer();
        lavaLampCom.setManName("lavalamp.com");
        LavaLamp greenwilly = new LavaLamp();
        greenwilly.setLavaName("Green Willy");
        greenwilly.setType("Large");
        greenwilly.setWaxColor("Green");
        greenwilly.setLiquidColor("Clear");
        greenwilly.setPrice(27.99);
        greenwilly.setHeight(16);
        greenwilly.setWidth(3.5);
        greenwilly.setId(6);
        greenwilly.setCostBook(new SimpleCostBook(greenwilly.getPrice()));
        greenwilly.setManufacturer(lavaLampCom);
        greenwilly.setManId(1);
        greenwilly.setSku(6666);
        lamps.add(greenwilly);
        try {
        PrintWriter out = response.getWriter();
        out.write(new Gson().toJson(lamps));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Answer 1

验证您是否正确设置了类，例如：

<servlet>
    <servlet-name>MyServletClass</servlet-name>
    <servlet-class>myPackage.mySubPackage.myClass</servlet-class>
</servlet>

我在本教程中找到了JPS和Servlet的完整示例，以及如何修改web.xml文件。所有代码都可用，所以我认为它可以帮助您：http://www.ibm.com/developerworks/java/library/j-hangman-app/index.html