table.java

来自「100多M的J2EE培训内容」· Java 代码 · 共 87 行

package tag;

import java.util.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import java.io.*;
public class table extends TagSupport {
private Iterator iterator;
private String items;
private String var;
//设置表头
private String header;

private StringBuffer sbTable=new StringBuffer("");
private int numCols=0;
private int ctr=0;

private JspWriter out;
public void setItems(String items) {
this.items = items;
}
public void setHeader(String header){
    this.header=header;
}
public void setVar(String var) {
this.var = var;
}
public int doStartTag( ) throws JspTagException {
    out=pageContext.getOut();
    //render the table header with column names
    sbTable.append("<table border='1' cellspacing='1' cellpadding='0' bgcolor='#DDDDDD' width='100%'><tr>");
    String[] colNames=(String[])pageContext.findAttribute(header);
    if (colNames == null) {
      throw new JspTagException("没有读取到表头设置信息");
    }
    numCols=colNames.length;
    for(int i=0;i<numCols;i++){
      sbTable.append("<td>"+colNames[i]+"</td>");
    }
    sbTable.append("</tr><tr>");
    //get table data
    Collection coll = (Collection) pageContext.findAttribute(items);
    if (coll == null) {
      try {
        out.println("没有相关数据内容");
      }
      catch (IOException ex) {
      }
       return SKIP_BODY;
    }
    iterator = coll.iterator();
    if (iterator.hasNext( )) {
//  pageContext.setAttribute(var, iterator);
  return EVAL_BODY_INCLUDE;
  }
  else {
  return SKIP_BODY;
  }
  }
  public int doAfterBody( ) {

  if (iterator.hasNext( )) {
  ctr++;
//  pageContext.setAttribute(var, iterator.next( ));
  //need start a new row
  // QQQ　what if numCols ==1
  sbTable.append("<td>"+(String)iterator.next()+"</td>");
  if((ctr%numCols)==0){
  System.out.println(ctr+"--"+numCols);
  sbTable.append("</tr><tr>");
  }

  return EVAL_BODY_AGAIN;
  }
  else {
  //finish render table data
  sbTable.append("</tr></table>");
//  System.out.println(sbTable);
  try {
    out.print(sbTable);
  }
  catch (IOException ex) {
  }
  return SKIP_BODY;
  }
  }
}