displaycodetag.java

一个关于tlms的一个小程序 看看能否帮助到别人

package com.szmx.tlms.admin.web.tag;

import com.szmx.framework.spring.context.ApplicationContextUtil;
import com.szmx.tlms.admin.service.CodeService;
import com.szmx.tlms.admin.model.Code;

import javax.servlet.jsp.tagext.TagSupport;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import java.io.IOException;
import java.util.List;
import java.util.Iterator;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.displaytag.tags.el.ExpressionEvaluator;

public class DisplayCodeTag extends TagSupport {
    private final Log log = LogFactory.getLog(getClass());
    private String codeType;
    private String codeValue;
    private String lang;
    private String selectedValue;
    private static final int DISPLAY_ONECODE = 0;
    private static final int DISPLAY_CHILDCODES = 1;

    public DisplayCodeTag() {
        this.lang = "CN";
    }

    public String getCodeType() {
        return codeType;
    }

    public void setCodeType(String codeType) {
        this.codeType = codeType;
    }

    public String getLang() {
        return lang;
    }

    public void setLang(String lang) {
        this.lang = lang;
    }

    public String getCodeValue() {
        return codeValue;
    }

    public void setCodeValue(String codeValue) {
        this.codeValue = codeValue;
    }

    public String getSelectValue() {
        return this.selectedValue;
    }

    public void setSelectValue(String value) {
        this.selectedValue = value;
    }

    private void evalParams(int dispType) throws JspException {
        ExpressionEvaluator eval = new ExpressionEvaluator(this, pageContext);
        if (dispType == DISPLAY_ONECODE) {
            this.codeValue = eval.evalString("codeValue", this.codeValue);
            this.codeType = eval.evalString("codeType", this.codeType);
        }
        if (dispType == DISPLAY_CHILDCODES) {
            this.codeType = eval.evalString("codeType", this.codeType);
            if (selectedValue != null) {
                this.selectedValue = eval.evalString("selectValue", this.selectedValue);
            }
        }
    }

    private int checkDisplayType() {
        if (codeValue == null || codeValue.equals("")) {
            return DISPLAY_CHILDCODES;
        } else
            return DISPLAY_ONECODE;
    }

    public int doStartTag() throws JspException {
        CodeService service = (CodeService) ApplicationContextUtil.getBean("codeService");
        int displayType = checkDisplayType();
        evalParams(displayType);
        switch (displayType) {
            case DISPLAY_ONECODE:
                Code code;
                try {
                    code = service.getCodeByTypeAndValue(codeType, codeValue);
                } catch (Exception e) {
                    log.error(e);
                    throw new JspException(e);
                }
                if (code != null) {
                    JspWriter out = pageContext.getOut();
                    try {
                        if (lang.equals("CN"))
                            out.print(code.getCodeCnDesc());
                        else
                            out.print(code.getCodeEnDesc());
                    } catch (IOException e) {
                        log.error(e);
                        throw new JspException(e);
                    }
                }
                break;
            case DISPLAY_CHILDCODES:
                try {
                    List codeList = service.getCodesByCodeType(codeType);
                    JspWriter out = pageContext.getOut();
                    for (Iterator i = codeList.iterator(); i.hasNext();) {
                        Code co = (Code) i.next();
                        StringBuffer html = new StringBuffer();
                        if (lang.equals("CN")) {
                            html.append("<option value='").append(co.getCodeValue()).append("' ");
                            if (selectedValue != null && selectedValue.equals(co.getCodeValue())) {
                                html.append("selected");
                            }
                            html.append(">").append(co.getCodeCnDesc()).append("</option>");
                        } else {
                            html.append("<option value='").append(co.getCodeValue()).append("' ");
                            if (selectedValue != null && selectedValue.equals(co.getCodeValue())) {
                                html.append("selected");
                            }
                            html.append(">").append(co.getCodeEnDesc()).append("</option>");
                        }
                        out.print(html);
                    }
                } catch (Exception e) {
                    log.error(e);
                    throw new JspException(e);
                }
                break;
            default:
                break;
        }
        return super.doStartTag();
    }
}