Struts2的类型转换
使用标签
注意：Struts2使用标签库找不到URI:[struts-tags]的taglib[s]问题解决
新建 login2.jsp 文件，内容如下：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Struts2.3 Login2</title>
</head>
<body>
<s:form action="login">
<s:textfield name="username" label="username"></s:textfield>
<s:textfield name="password" label="password"></s:textfield>
<s:submit label="submit"></s:submit>
</s:form>
</body>
</html>
查看结果：
在 Action 中使用 ActionSupport
新增页面
login3.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Struts2.3 Login3</title>
</head>
<body>
<s:form action="login3">
<s:textfield name="username" label="username"></s:textfield>
<s:textfield name="password" label="password"></s:textfield>
<s:submit label="submit"></s:submit>
</s:form>
</body>
</html>
LoginAction3.java
package space.terwer;
import org.apache.commons.lang3.StringUtils;
import com.opensymphony.xwork2.ActionSupport;
public class LoginAction3 extends ActionSupport{
private String username;
private String password;
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 void validate() {
if(StringUtils.isBlank(this.getUsername())) {
this.addFieldError("username", "username required");
}
if(StringUtils.isBlank(this.getPassword())) {
this.addFieldError("password", "password required");
}
}
public String execute() {
return "success";
}
}
修改 struts.xml 添加校验跳转 input
struts.xml
<!-- 使用ActionSupport -->
<action name="login3" class="space.terwer.LoginAction3">
<result name="success">/result.jsp</result>
<result name="input">/login3.jsp</result>
</action>
效果
业务验证
在 LoginAction2.java 的 execute() 方法添加验证逻辑
public String execute() {
if("hello".equals(this.getUsername().trim()) && "world".equals(this.getPassword().trim())){
return "success";
}
this.addFieldError("username", "username or password error");
return "failer";
}
在 struts.xml 加入跳转逻辑
<!-- 使用ActionSupport -->
<action name="login3" class="space.terwer.LoginAction3">
<result name="success">/result.jsp</result>
<result name="input">/login3.jsp</result>
<result name="failer">/login3.jsp</result>
</action>
效果
注意：result.jsp 里面的两种写法等价。
username:${requestScope.username}<br />
password:${requestScope.password }
username:<%=request.getParameter("username") %><br />
password:<%=request.getParameter("password") %>
类型转换深入
新建一个 input.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Struts2.3 convert test</title>
</head>
<body>
<h3 style="color:red;">使用逗号将点的两个坐标分隔开</h3>
<s:form action="pointConverter">
<s:textfield name="point" label="point"></s:textfield>
<s:textfield name="age" label="age"></s:textfield>
<s:textfield name="username" label="username"></s:textfield>
<s:textfield name="date" label="birthday"></s:textfield>
<s:submit value="Submit"></s:submit>
</s:form>
</body>
</html>
Point 对象
新建一个 bean 为 Point.java
package space.terwer.bean;
public class Point {
private Integer x;
private Integer y;
public Integer getX() {
return x;
}
public void setX(Integer x) {
this.x = x;
}
public Integer getY() {
return y;
}
public void setY(Integer y) {
this.y = y;
}
}
OGNL 官网
https://commons.apache.org/proper/commons-ognl/
新的官网
https://github.com/apache/commons-ognl
新建一个类型转换器类 PointConverter
package space.terwer.converter;
import java.util.Map;
import ognl.DefaultTypeConverter;
import space.terwer.bean.Point;
public class PointConverter extends DefaultTypeConverter {
@Override
public Object convertValue(Map context, Object value, Class toType) {
if (Point.class == toType) {
Point point = new Point();
String[] str = (String[]) value;
String[] paramValues = str[0].split(",");
Integer x = new Integer(paramValues[0]);
Integer y = new Integer(paramValues[1]);
point.setX(x);
point.setY(y);
return point;
}
if (String.class == toType) {
Point point = (Point) value;
int x = point.getX();
int y = point.getY();
String result = "[x=" + x + ", y=" + y + "]";
return result;
}
return null;
}
}
新建一个 PointAction 处理类
package space.terwer.action;
import java.util.Date;
import com.opensymphony.xwork2.ActionSupport;
import space.terwer.bean.Point;
public class PointAction extends ActionSupport {
private Point point;
private Integer age;
private String username;
private Date date;
public Point getPoint() {
return point;
}
public void setPoint(Point point) {
this.point = point;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public Date getDate() {
return date;
}
public void setDate(Date date) {
this.date = date;
}
@Override
public String execute() throws Exception {
return SUCCESS;
}
}
struts.xml 添加处理流程配置：
<action name="pointConverter" class="space.terwer.action.PointAction">
<result name="success">/output.jsp</result>
</action>
新增转换器配置
必须在当前 Action 同级目录新建 Action类名-conversion.properties ，例如：
PointAction-conversion.properties
内容为 需要转换的属性名称 和 转换器全路径 ，例如本例子内容如下：
point=space.terwer.converter.PointConverter
重启服务器。
特别指出：转换器文件前面必须是Action类名，后缀必须是：
-conversion.properties
output.jsp 显示页面
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Point result</title>
</head>
<body>
point:<s:property value="point" /><br/>
age:<s:property value="age" /><br/>
username:<s:property value="username" /><br/>
date:<s:property value="date" />
</body>
</html>
查看效果
