optiontag.java

来自「21天精通Java,这是一本英文书」· Java 代码 · 共 47 行

package web;

import java.io.*;
import java.util.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;

public class OptionTag extends TagSupport {
	private String[] selected = new String[0];

	public void setSelected (String[] selected) {
		this.selected = selected;
	}

	public String[] getSelected () {
		return selected;
	}

	public void setDefault (String selected) {
		this.selected = new String[]{selected};
	}

	public String getDefault () {
		return selected[0];
	}

	public int doStartTag() throws JspTagException {
		try {
			ForEachTag loop = (ForEachTag)findAncestorWithClass(this, ForEachTag.class);
			String value = loop.getCurrentValue();
			for (int i=0; i<selected.length; i++) {
				if (value.equals(selected[i])) {
					pageContext.getOut().print("<OPTION selected>"+value);
					return SKIP_BODY;
				}
			}
			pageContext.getOut().print("<OPTION>"+value);
		}
		catch (IOException ex) {
			throw new JspTagException("OptionTag: "+ex);
		}
		return SKIP_BODY;
	 }

}