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>