struts2 Preparable接口
1. 引言
开发人员在使用struts2开发中，把CRUD方法放在一个action类中，就必定会涉及到一些数据准备的事情；用Preparable接口就再合适不过了。
2. 概述
开发人员在使用struts2涉及到一些数据准备的事情；用Preparable接口，实现这个接口的prepare()方法，这个方法会在action类的所有方法执行前执行，另外开发人员也可以按照它的规则来写一些其它形式的prepare方法，例如aciton中有一个方法叫saveTest(),那么我们可以实现一个prepareSaveTest方法，这样在saveTest ()执行前，会执行prepareSaveTest ()方法。
3. 例子
PrepareTest.java
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import com.neusoft.mid.bip.adaper.service.ServiceInvoker;
import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.Preparable;
public class PrepareTest extends ActionSupport implements Preparable {
private static final long serialVersionUID = 1L;
/**
* 日志输出类
*/
private final static Log log = LogFactory.getLog(ServiceInvoker.class);
/**
* 公共的list
*/
private List<String> list = new ArrayList<String>();
/**
* 添加的list
*/
private List<String> listAdd = new ArrayList<String>();
/**
* 列表的list
*/
private List<String> listShow = new ArrayList<String>();
public String saveTest() {
return SUCCESS;
}
public String listTest() {
return SUCCESS;
}
@Override
public void prepare() throws Exception {
log.info("prepare init......");
list.add("1");
list.add("2");
list.add("3");
}
public void prepareSaveTest() {
log.info("prepareSaveTest load......");
listAdd.add("a");
listAdd.add("b");
listAdd.add("c");
}
public void prepareListTest() {
log.info("prepareListTest load.......");
listShow.add("*");
listShow.add("-");
listShow.add("+");
}
public List<String> getList() {
return list;
}
public void setList(List<String> list) {
this.list = list;
}
public List<String> getListAdd() {
return listAdd;
}
public void setListAdd(List<String> listAdd) {
this.listAdd = listAdd;
}
public List<String> getListShow() {
return listShow;
}
public void setListShow(List<String> listShow) {
this.listShow = listShow;
}
}
Save 页面
<%@ page language="java" pageEncoding="utf-8"%>
<%@ include file="/WEB-INF/bip/pages/commons/taglibs.jsp"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<%@ include file="/WEB-INF/bip/pages/commons/jslibs.jsp"%>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/smap/smap.js"></script>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/smap/util.js"></script>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/jsTree1.0/jquery.jstree.js"></script>
</head>
<body>
<div align ="center" style="margin-top:200px;">
<font size="5">save ...</font><br/>
prepare list 遍历：
<s:iterator value="list" status="sp" id="com">
<s:property value="com"/>...
</s:iterator>
<br/>
prepare listShow 遍历：
<s:iterator value="listShow" status="sp" id="show">
<s:property value="show"/>...
</s:iterator>
<br/>
prepare listAdd 遍历：
<s:iterator value="listAdd" status="sp" id="add">
<s:property value="add"/>...
</s:iterator>
</div>
<div align="right" style="margin-top:75px;margin-right:70px;">
<a href="list.shtml"/>list</a>
</div>
</body>
</html>
List 页面
<%@ page language="java" pageEncoding="utf-8"%>
<%@ include file="/WEB-INF/bip/pages/commons/taglibs.jsp"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<%@ include file="/WEB-INF/bip/pages/commons/jslibs.jsp"%>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/smap/smap.js"></script>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/smap/util.js"></script>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/jsTree1.0/jquery.jstree.js"></script>
</head>
<body>
<div align ="center" style="margin-top:200px;">
<font size="5">list ...</font><br/>
prepare list 遍历：
<s:iterator value="list" status="sp" id="com">
<s:property value="com"/>...
</s:iterator>
<br/>
prepare listShow 遍历：
<s:iterator value="listShow" status="sp" id="show">
<s:property value="show"/>...
</s:iterator>
<br/>
prepare listAdd 遍历：
<s:iterator value="listAdd" status="sp" id="add">
<s:property value="add"/>...
</s:iterator>
</div>
<div align="right" style="margin-top:75px;margin-right:70px;">
<a href="save.shtml"/>save</a>
</div>
</body>
</html>
Spring 文件配置
<bean id="aaa" class="com.neusoft.mid.bip.aaa.test.PrepareTest" scope="prototype"></bean>
Struts 文件配置
<package name="aaa" namespace="/aaa" extends="mat-default">
<action name="save" class="aaa" method="saveTest">
<result name="success">
/WEB-INF/bip/pages/aaa/save.jsp
</result>
</action>
<action name="list" class="aaa" method="listTest">
<result name="success">
/WEB-INF/bip/pages/aaa/list.jsp
</result>
</action>
</package>
开发人员在使用struts2开发中，把CRUD方法放在一个action类中，就必定会涉及到一些数据准备的事情；用Preparable接口就再合适不过了。
2. 概述
开发人员在使用struts2涉及到一些数据准备的事情；用Preparable接口，实现这个接口的prepare()方法，这个方法会在action类的所有方法执行前执行，另外开发人员也可以按照它的规则来写一些其它形式的prepare方法，例如aciton中有一个方法叫saveTest(),那么我们可以实现一个prepareSaveTest方法，这样在saveTest ()执行前，会执行prepareSaveTest ()方法。
3. 例子
PrepareTest.java
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import com.neusoft.mid.bip.adaper.service.ServiceInvoker;
import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.Preparable;
public class PrepareTest extends ActionSupport implements Preparable {
private static final long serialVersionUID = 1L;
/**
* 日志输出类
*/
private final static Log log = LogFactory.getLog(ServiceInvoker.class);
/**
* 公共的list
*/
private List<String> list = new ArrayList<String>();
/**
* 添加的list
*/
private List<String> listAdd = new ArrayList<String>();
/**
* 列表的list
*/
private List<String> listShow = new ArrayList<String>();
public String saveTest() {
return SUCCESS;
}
public String listTest() {
return SUCCESS;
}
@Override
public void prepare() throws Exception {
log.info("prepare init......");
list.add("1");
list.add("2");
list.add("3");
}
public void prepareSaveTest() {
log.info("prepareSaveTest load......");
listAdd.add("a");
listAdd.add("b");
listAdd.add("c");
}
public void prepareListTest() {
log.info("prepareListTest load.......");
listShow.add("*");
listShow.add("-");
listShow.add("+");
}
public List<String> getList() {
return list;
}
public void setList(List<String> list) {
this.list = list;
}
public List<String> getListAdd() {
return listAdd;
}
public void setListAdd(List<String> listAdd) {
this.listAdd = listAdd;
}
public List<String> getListShow() {
return listShow;
}
public void setListShow(List<String> listShow) {
this.listShow = listShow;
}
}
Save 页面
<%@ page language="java" pageEncoding="utf-8"%>
<%@ include file="/WEB-INF/bip/pages/commons/taglibs.jsp"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<%@ include file="/WEB-INF/bip/pages/commons/jslibs.jsp"%>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/smap/smap.js"></script>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/smap/util.js"></script>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/jsTree1.0/jquery.jstree.js"></script>
</head>
<body>
<div align ="center" style="margin-top:200px;">
<font size="5">save ...</font><br/>
prepare list 遍历：
<s:iterator value="list" status="sp" id="com">
<s:property value="com"/>...
</s:iterator>
<br/>
prepare listShow 遍历：
<s:iterator value="listShow" status="sp" id="show">
<s:property value="show"/>...
</s:iterator>
<br/>
prepare listAdd 遍历：
<s:iterator value="listAdd" status="sp" id="add">
<s:property value="add"/>...
</s:iterator>
</div>
<div align="right" style="margin-top:75px;margin-right:70px;">
<a href="list.shtml"/>list</a>
</div>
</body>
</html>
List 页面
<%@ page language="java" pageEncoding="utf-8"%>
<%@ include file="/WEB-INF/bip/pages/commons/taglibs.jsp"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<%@ include file="/WEB-INF/bip/pages/commons/jslibs.jsp"%>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/smap/smap.js"></script>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/smap/util.js"></script>
<script type="text/javascript"
src="<%=request.getContextPath()%>/bip/scripts/jsTree1.0/jquery.jstree.js"></script>
</head>
<body>
<div align ="center" style="margin-top:200px;">
<font size="5">list ...</font><br/>
prepare list 遍历：
<s:iterator value="list" status="sp" id="com">
<s:property value="com"/>...
</s:iterator>
<br/>
prepare listShow 遍历：
<s:iterator value="listShow" status="sp" id="show">
<s:property value="show"/>...
</s:iterator>
<br/>
prepare listAdd 遍历：
<s:iterator value="listAdd" status="sp" id="add">
<s:property value="add"/>...
</s:iterator>
</div>
<div align="right" style="margin-top:75px;margin-right:70px;">
<a href="save.shtml"/>save</a>
</div>
</body>
</html>
Spring 文件配置
<bean id="aaa" class="com.neusoft.mid.bip.aaa.test.PrepareTest" scope="prototype"></bean>
Struts 文件配置
<package name="aaa" namespace="/aaa" extends="mat-default">
<action name="save" class="aaa" method="saveTest">
<result name="success">
/WEB-INF/bip/pages/aaa/save.jsp
</result>
</action>
<action name="list" class="aaa" method="listTest">
<result name="success">
/WEB-INF/bip/pages/aaa/list.jsp
</result>
</action>
</package>