dwr入门实例二

dwr怎么样把java的类型和javascript的类型关联起来的呢？那么这就要靠dwr强大的converter转换器了。dwr集成了很多已经实现了的类型转换器了，比如基本类型，javabean等等。

在这org.directwebremoting个包下面有个dwr.xml就是dwr框架的一些默认配置，里面配置了很多转换器。

当然也可以自己实现转换器，实现接口Converter就行了。

官方的解释：

http://directwebremoting.org/dwr/documentation/server/configuration/dwrxml/converters/index.html

下面是默认的dwr.xml：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE dwr PUBLIC
    "-//GetAhead Limited//DTD Direct Web Remoting 3.0//EN"
    "http://getahead.org/dwr/dwr30.dtd">
<dwr>
  <init>
    <creator id="none" class="org.directwebremoting.create.NullCreator"/>
    <creator id="new" class="org.directwebremoting.create.NewCreator"/>
    <creator id="pageflow" class="org.directwebremoting.beehive.PageFlowCreator"/>
    <creator id="spring" class="org.directwebremoting.spring.SpringCreator"/>
    <creator id="script" class="org.directwebremoting.create.ScriptedCreator"/>
    <creator id="struts" class="org.directwebremoting.struts.StrutsCreator"/>
    <!--
    These are now in the noncla module
    <creator id="jsf" class="org.directwebremoting.faces.JsfCreator"/>
    <creator id="ejb3" class="org.directwebremoting.create.Ejb3Creator"/>
    -->
    <converter id="null" class="org.directwebremoting.convert.NullConverter"/>
    <converter id="enum" class="org.directwebremoting.convert.EnumConverter"/>
    <converter id="primitive" class="org.directwebremoting.convert.PrimitiveConverter"/>
    <converter id="bignumber" class="org.directwebremoting.convert.BigNumberConverter"/>
    <converter id="string" class="org.directwebremoting.convert.StringConverter"/>
    <converter id="array" class="org.directwebremoting.convert.ArrayConverter"/>
    <converter id="map" class="org.directwebremoting.convert.MapConverter"/>
    <converter id="collection" class="org.directwebremoting.convert.CollectionConverter"/>
    <converter id="date" class="org.directwebremoting.convert.DateConverter"/>
    <converter id="dom" class="org.directwebremoting.convert.DOMConverter"/>
    <converter id="dom4j" class="org.directwebremoting.convert.DOM4JConverter"/>
    <converter id="jdom" class="org.directwebremoting.convert.JDOMConverter"/>
    <converter id="xom" class="org.directwebremoting.convert.XOMConverter"/>
    <converter id="servlet" class="org.directwebremoting.convert.ServletConverter"/>
    <converter id="bean" class="org.directwebremoting.convert.BeanConverter"/>
    <converter id="object" class="org.directwebremoting.convert.ObjectConverter"/>
    <converter id="hibernate2" class="org.directwebremoting.hibernate.H2BeanConverter"/>
    <converter id="hibernate3" class="org.directwebremoting.hibernate.H3BeanConverter"/>
    <converter id="url" class="org.directwebremoting.convert.URLConverter"/>
    <converter id="exception" class="org.directwebremoting.convert.ExceptionConverter"/>
    <converter id="miniException" class="org.directwebremoting.convert.MinimalistExceptionConverter"/>
    <converter id="file" class="org.directwebremoting.convert.FileConverter"/>
    <converter id="context" class="org.directwebremoting.convert.ContextConverter"/>
    <converter id="stringWrapper" class="org.directwebremoting.convert.StringWrapperConverter"/>
    <converter id="raw" class="org.directwebremoting.convert.RawConverter"/>
    <converter id="proxyFunction" class="org.directwebremoting.convert.JavascriptFunctionConverter"/>
    <converter id="proxyObject" class="org.directwebremoting.convert.JavascriptObjectConverter"/>
    <converter id="proxyInterface" class="org.directwebremoting.convert.ProxyInterfaceConverter"/>
    <converter id="locale" class="org.directwebremoting.convert.LocaleConverter"/>
    <converter id="currency" class="org.directwebremoting.convert.CurrencyConverter"/>
    <converter id="jsx3uri" class="jsx3.net.URIResolverConverter"/>
    <converter id="jsx3doc" class="jsx3.xml.CdfDocumentConverter"/>
  </init>
  <allow>
    <convert converter="null" match="void"/>
    <convert converter="null" match="java.lang.Void"/>
    <convert converter="miniException" match="java.lang.Throwable"/>
    <convert converter="primitive" match="boolean"/>
    <convert converter="primitive" match="byte"/>
    <convert converter="primitive" match="short"/>
    <convert converter="primitive" match="int"/>
    <convert converter="primitive" match="long"/>
    <convert converter="primitive" match="float"/>
    <convert converter="primitive" match="double"/>
    <convert converter="primitive" match="char"/>
    <convert converter="primitive" match="java.lang.Boolean"/>
    <convert converter="primitive" match="java.lang.Byte"/>
    <convert converter="primitive" match="java.lang.Short"/>
    <convert converter="primitive" match="java.lang.Integer"/>
    <convert converter="primitive" match="java.lang.Long"/>
    <convert converter="primitive" match="java.lang.Float"/>
    <convert converter="primitive" match="java.lang.Double"/>
    <convert converter="primitive" match="java.lang.Character"/>
    <convert converter="bignumber" match="java.math.BigInteger"/>
    <convert converter="bignumber" match="java.math.BigDecimal"/>
    <convert converter="string" match="java.lang.String"/>
    <convert converter="date" match="java.util.Date"/>
    <convert converter="date" match="java.sql.Date"/>
    <convert converter="date" match="java.sql.Time"/>
    <convert converter="date" match="java.sql.Timestamp"/>
    <convert converter="date" match="java.util.Calendar"/>
    <convert converter="url" match="java.net.URL"/>
    <convert converter="locale" match="java.util.Locale"/>
    <convert converter="currency" match="java.util.Currency"/>
    <convert converter="array" match="[Z"/>
    <convert converter="file" match="[B"/>
    <convert converter="array" match="[S"/>
    <convert converter="array" match="[I"/>
    <convert converter="array" match="[J"/>
    <convert converter="array" match="[F"/>
    <convert converter="array" match="[D"/>
    <convert converter="array" match="[C"/>
    <convert converter="array" match="[L*"/>
    <!--
    The catch for the next 2 is that we really mean java.util.Collection<String>
    and java.util.Map<String, String> but we need to do more work before this
    syntax is enabled
    -->
    <convert converter="collection" match="java.util.Collection"/>
    <convert converter="map" match="java.util.Map"/>
    <convert converter="dom" match="org.w3c.dom.Node"/>
    <convert converter="dom" match="org.w3c.dom.Element"/>
    <convert converter="dom" match="org.w3c.dom.Document"/>
    <convert converter="dom4j" match="org.dom4j.Document"/>
    <convert converter="dom4j" match="org.dom4j.Element"/>
    <convert converter="dom4j" match="org.dom4j.Node"/>
    <convert converter="jdom" match="org.jdom.Document"/>
    <convert converter="jdom" match="org.jdom.Element"/>
    <convert converter="xom" match="nu.xom.Document"/>
    <convert converter="xom" match="nu.xom.Element"/>
    <convert converter="xom" match="nu.xom.Node"/>
    <convert converter="servlet" match="javax.servlet.ServletConfig"/>
    <convert converter="servlet" match="javax.servlet.ServletContext"/>
    <convert converter="servlet" match="javax.servlet.http.HttpServletRequest"/>
    <convert converter="servlet" match="javax.servlet.http.HttpServletResponse"/>
    <convert converter="servlet" match="javax.servlet.http.HttpSession"/>
    <convert converter="file" match="java.io.InputStream"/>
    <convert converter="file" match="java.awt.image.BufferedImage"/>
    <convert converter="jsx3uri" match="jsx3.net.URIResolver"/>
    <convert converter="jsx3doc" match="jsx3.xml.CdfDocument"/>
    <convert converter="exception" match="org.directwebremoting.io.DwrConvertedException"/>
    <convert converter="file" match="org.directwebremoting.io.FileTransfer"/>
    <convert converter="bean" match="org.directwebremoting.io.Item"/>
    <convert converter="bean" match="org.directwebremoting.io.ItemUpdate">
      <param name="constructor" value="String itemId, String attribute, org.directwebremoting.io.RawData newValue"/>
    </convert>
    <convert converter="bean" match="org.directwebremoting.io.MatchedItems"/>
    <convert converter="proxyFunction" match="org.directwebremoting.io.JavascriptFunction"/>
    <convert converter="proxyObject" match="org.directwebremoting.io.JavascriptObject"/>
    <convert converter="raw" match="org.directwebremoting.io.RawData"/>
    <convert converter="bean" match="org.directwebremoting.io.StoreRegion">
      <param name="constructor" value="int start, int count, java.util.List sort, java.util.Map query"/>
    </convert>
    <convert converter="proxyInterface" match="org.directwebremoting.io.StoreChangeListener"/>
    <convert converter="null" match="org.directwebremoting.datasync.StoreProvider"/>
    <convert converter="bean" match="org.directwebremoting.jsonrpc.io.JsonRpcError"/>
    <convert converter="bean" match="org.directwebremoting.jsonrpc.io.JsonRpcResponse"/>
    <convert converter="bean" match="org.directwebremoting.io.SortCriterion">
      <param name="constructor" value="String attribute, boolean descending"/>
    </convert>
    <convert converter="stringWrapper" match="org.directwebremoting.io.StringWrapper"/>
    <!--
    <convert converter="context" match="org.directwebremoting.io.Context"/>
    -->
    <create creator="new" javascript="__System" scope="application">
      <!-- ExportUtil.isSystemClass assumes the name __System -->
      <param name="class" value="org.directwebremoting.export.System"/>
      <param name="hidden" value="true"/>
    </create>
    <create creator="new" javascript="__Data" scope="application">
      <param name="class" value="org.directwebremoting.export.Data"/>
      <param name="hidden" value="true"/>
    </create>
  </allow>
</dwr>

这里主要用到两个标签，

1.converter标签用在init标签里面注册类型转换器。

2.convert 这个标签是引用converter，属性converter的值就是converter的id属性的值。

match属性就是bean的路径包括完整的报名。

下面我们举个实例：

java类：

package test;
public class UserBean {
	private String username;
	private String password;
	public UserBean() {
		System.out.println("userbean created....");
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	@Override
	public String toString() {
		return username + ";" + password;
	}
}

package test;
public class UserService {
	public String addUser(UserBean ub) {
		System.out.println(ub.toString());
		return ub.toString();
	}
}

前台js调用方法addUser添加user，addUser方法的参数类型是UserBean。

js文件：

 <mce:script type='text/javascript' src="/dwr3.0/dwr/interface/UserService.js" mce_src="dwr3.0/dwr/interface/UserService.js"><!--
        
// --></mce:script>
        <mce:script type='text/javascript' src="/dwr3.0/dwr/engine.js" mce_src="dwr3.0/dwr/engine.js"><!--
        
// --></mce:script>
        <mce:script type="text/javascript"><!--
            var p = {
                username: "lazy",
                password: "123456"
            };
            UserService.addUser(p, function(str){
                alert(str);
            });
        
// --></mce:script>

dwr.xml文件：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE dwr PUBLIC
 "-//GetAhead Limited//DTD Direct Web Remoting 3.0//EN"
 "http://getahead.org/dwr/dwr30.dtd">
<dwr>
   
    <allow>
        <create creator="new" javascript="Demo">
            <param name="class" value="java.lang.String"/>
        </create>
        <create creator="new" javascript="UserService">
            <param name="class" value="test.UserService"/>
        </create>
       
        <convert converter="bean" match="test.UserBean"/>
    </allow>
</dwr>