columntag.java

java版源代码,里面包含很多源代码,大家可以看看.

package com.trulytech.mantis.tag;

import java.io.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import java.util.ArrayList;
import com.trulytech.mantis.result.DBColumn;

/**
 *
 * <p>Title: Mantis</p>
 *
 * <p>Description: 根据指定的列值获得DBColumn中的值</p>
 *
 * <p>Copyright: Copyright (c) 2002</p>
 *
 * <p>Company: </p>
 *
 * @author Wang Xian
 * @version 1.1
 */

/*例如********************************************************
 <bean:foreach name="Result">
   <tr>
   <td width="100%"><bean:value col="0" /></td>
   </tr>
 </bean:foreach>
 或者
 <bean:foreach name="Result">
   <tr>
   <td width="100%"><bean:value col="0" type="html" /></td>
   </tr>
 </bean:foreach>

 */
public class ColumnTag
    extends TagSupport {

  private int Col = 0;

  //输出格式
  private String Type = "";

  /**
   * 覆盖doStartTag方法
   * @return int
   * @throws JspTagException
   */
  public int doStartTag() throws JspTagException {
    return EVAL_BODY_INCLUDE;
  }

  /**
   * 结束tag
   * @return int
   * @throws JspTagException
   */
  public int doEndTag() throws JspTagException {
    try {
      if (this.pageContext.findAttribute("array") != null)

        if (this.pageContext.findAttribute("array") instanceof ArrayList)
          if (Col >= ( (ArrayList)this.pageContext.findAttribute("array")).size())
            this.pageContext.getOut().write("");
          else
          if (Type.equalsIgnoreCase("html"))

            this.pageContext.getOut().write(com.trulytech.mantis.system.
                                            Properties.HTMLEncoder( ( (DBColumn) ( (
                ArrayList)this.
                pageContext.findAttribute("array")).get(Col)).Value));

          else

            this.pageContext.getOut().write( ( (DBColumn) ( (ArrayList)this.
                pageContext.findAttribute("array")).get(Col)).Value);

        else
          this.pageContext.getOut().write("");
      else
        this.pageContext.getOut().write("");

    }
    catch (IOException e) {
      throw new JspTagException("Fatal error");
    }
    return EVAL_PAGE;
  }

  /**
   * 设置列值
   * @param Col int
   */
  public void setCol(int Col) {
    this.Col = Col;
  }

  public void setType(String Type) {
    if (Type == null)
      this.Type = "";
    else
      this.Type = Type;
  }

}