1. 新建RepeatSampleTag类，代码如下：
2. 配置xml文件（如何配置xml），部分代码如下：
3. 调用标签，部分代码如下：
JSP简单标签的开发
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package bid.zhazhapan.fims.tag;
import java.io.IOException;
import java.io.StringWriter;
import javax.servlet.jsp.JspContext;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.JspFragment;
import javax.servlet.jsp.tagext.SimpleTagSupport;
public class RepeatSampleTag extends SimpleTagSupport {
private int num;// 定义属性
public void setNum(int num) {
this.num = num;
}
// 覆盖方法，标签的逻辑、迭代
public void doTag() throws JspException, IOException {
// 获得页面上下文对象
JspContext ctx = this.getJspContext();
// 获得封闭标签体对象
JspFragment fragment = this.getJspBody();
if (num > 0) {
// 定义一个字符流，用来接收标签体的内容
StringWriter writer = new StringWriter();
// 将标签体的内容输出到字符流中
fragment.invoke(writer);
// 从字符流中获得数据
String string = writer.getBuffer().toString();
for (int i = 1; i < num + 1; i++) {
ctx.getOut().write(i + "." + string.toUpperCase() + "<br/>");
}
} else {
// invoke()方法传入null值，采用默认的输出流
fragment.invoke(null);
}
}
}
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<javaee:tag>
<javaee:name>repeat</javaee:name>
<javaee:tag-class>bid.zhazhapan.fims.tag.RepeatSampleTag</javaee:tag-class>
<javaee:body-content>scriptless</javaee:body-content>
<javaee:attribute>
<javaee:name>num</javaee:name>
<javaee:required>true</javaee:required>
<javaee:rtexprvalue>true</javaee:rtexprvalue>
</javaee:attribute>
</javaee:tag>
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<mytag:repeat num="5">
hello world
</mytag:repeat>
