初步接触Java遇到的问题

注意：框架原因使用eclipse时需要先把jre改为jdk

使用一个框架首先要clean和install在强制更新

修改总框架的数据库用户和密码

然后更改mybatis.xml文件里的扫描dao的信息再改servlet.xml

里边的<context:component-scan base-package=””>

1.当网页请求不到地址时两种情况①页面地址写错②没有扫描到包

2.用注解是自动扫描扫描到的

3.分页的步骤：①在dao中继承GenericDao<T, Serializable>Serializable序列化ID意思在bean里边写 T是model给谁分页就写谁的model

②在bean中继承序列化通过序列化ID知dao中的序列化为*

③写sql语句

<select

id="searchPage" parameterType="com.eigpay.framework.student.webapp.searcher.StudentSearcherPage"

resultMap="StudentMap">

select *from Student

<where>

flag = 0

and name like CONCAT('%',#{stuName},'%')

</if>

</where>

</select>

注意： 如果mapper中代码写错的话会导致页面不能登录

④在searcher包里写一个*SearcherPage并继承Page<要分页的Model>并将parameterType的内容改为*SearcherPage地址 id不变

⑤在Service中写入Page<Student> studentSearcherPage(StudentSearcherPage studentSearcherPage);

在Service下的impl中写

@Override

public Page<Student> studentSearcherPage(StudentSearcherPage studentSearcherPage) {

// TODO Auto-generated method stub

studentSearcherPage.setPageSize(9);//表示每页存入几条

//返回的结果集

studentSearcherPage.setResult(stuDao.searchPage(studentSearcherPage));

return studentSearcherPage;

}

⑥在controller中写入代码

@RequestMapping("list")

public ModelAndView list(@ModelAttribute("studentSearcherPage")StudentSearcherPage studentSearcherPage){

return new ModelAndView("student/selectAll_list")

.addObject("studentSearcherPage", studentSearcherPage)//为了将页码、页数查询条件等返回给前台页面

.addObject("pageObj", stuService.studentSearcherPage(studentSearcherPage));//将查询的结果集返回给前台页面

}

⑦修改前台页面 items="${pageObj.result}" list存到了result里边

4.框架网页建菜单①新增资源②角色管理（给角色分配菜单）③配子菜单(路径：先写父级路径 URL：后台程序登录网页地址如（/StudentCol/list）)④角色管理（给角色分配菜单）

5.实现修改新增一个jsp步骤：

①修改jsp页面

②后台

注意：由于前台页面用的是form：form表单action="${ctx}/*"所以后台不能随便跳页面

@RequestMapping("manage")

public ModelAndView manage(@ModelAttribute("Student")Student stu){

return new ModelAndView("student/student_manage")

.addObject("student", stu);

}

6.下拉框实现（死的下拉框）：在需要下拉框的jsp写如

（<select name="sex" class="form-control" id="sex" validata-options="validType:'Require',msg:'不能为空'">

</select>）

7.下拉框实现（活的下拉框）：

①新建一个表

②在mapper中写查询表的sql

③写代码

④前台

<c:forEach items="${dept}" var="dept">

<option value="${dept.deptName}" <c:if test="${dept.deptName == student.dept}"> selected </c:if> >${dept.deptName}</option>

</c:forEach>

</select>

</div>

出现的错误：

一、Invalid bound statement (not found)错误

原因：1.<mapper namespace="me.tspace.pm.dao.UserDao">

mapper的namespace写的不对！！！注意系修改。

2.UserDao的方法在UserDao.xml中没有，然后执行UserDao的方法会报此（查询的名称与xml中的没有对上）

3. UserDao的方法返回值是List<User>,而select元素没有正确配置ResultMap,或者只配置ResultType!

4. 如果你确认没有以上问题,请任意修改下对应的xml文件,比如删除一个空行,保存.问题解决…

文件导出

一、 controller继承Basecontroller和admin的pom文件写

<groupId>eigpay-sdk</groupId>

<artifactId>excel</artifactId>

</dependency>

二、 Basecontroller中写

/**

* excel导出

* @param fileName 文件名称

* @param sheetName sheet页名称

* @param excelPojos excel数据

* @param request

* @param response

* @throws Exception

public void downLoadExcel(String fileName, String sheetName, List<?> excelPojos,HttpServletRequest request,HttpServletResponse response) throws Exception {

ArrayList<List<?>> datas = new ArrayList<>();

datas.add(excelPojos);

Component component = ExcelComponentsFactory.produce();

ExcelExportSetting excelExportSetting = new ExcelExportSetting();

excelExportSetting.setData(datas);

excelExportSetting.setExcelFileType(ExcelFileType.XLSX);

excelExportSetting.setSheetName(new String[] { sheetName });

File path = new File("." + File.separator + "file");

if (!path.exists())

path.mkdirs();

String filePathAndName = "." + File.separator + "file" + File.separator + fileName;

File file = new File(filePathAndName);

if (file.exists())

file.delete();

excelExportSetting.setExcelFilePath(filePathAndName);

component.exportList2Excel(excelExportSetting);

response.setContentType("text/html;charset=utf-8");

request.setCharacterEncoding("UTF-8");

java.io.BufferedInputStream bis = null;

java.io.BufferedOutputStream bos = null;

try {

long fileLength = file.length();

response.setContentType("application/x-msdownload;");

response.setHeader("Content-disposition",

"attachment; filename=" + new String(fileName.getBytes("utf-8"), "ISO8859-1"));

response.setHeader("Content-Length", String.valueOf(fileLength));

bis = new BufferedInputStream(new FileInputStream(filePathAndName));

bos = new BufferedOutputStream(response.getOutputStream());

byte[] buff = new byte[2048];

int bytesRead;

while (-1 != (bytesRead = bis.read(buff, 0, buff.length)))

bos.write(buff, 0, bytesRead);

} catch (Exception e) {

throw new Exception(e);

} finally {

if (bis != null) {

bis.close();

bis = null;

}

if (bos != null) {

bos.flush();

bos.close();

bos = null;

}

包含日期的导出

三、写一个关于导出所需要的model类

四、 controller中写

/**

* 导出项目信息表

* @throws Exception

* @return /projectInfoManage/projectInfo/exportprojectBasicInfo

@RequestMapping(value = "/exportprojectBasicInfo", method = RequestMethod.POST)

private void exportprojectBasicInfo(ProjectStaticManagePageSearcher seacher, HttpServletRequest request,HttpServletResponse response) throws Exception {

//1.查项目信息数据列表

List<ProjectInfo> ProjectInfoList = projectStaticInfoDao.getExcelData(seacher);

//2.data pojos to excel pojos

List<Object> ProjectInfo = projectStaticManage.downloadProjectInfo(ProjectInfoList);

//3.生成文件名

StringBuffer stringBuffer = new StringBuffer("项目信息-");

stringBuffer.append(new SimpleDateFormat("yyyyMMdd").format(new Date()));

stringBuffer.append(".xlsx");

String fileName = stringBuffer.toString();

//4.调方法

super.downLoadExcel(fileName, "项目信息", ProjectInfo, request, response);

}

五、ManageImpl中写

@Override

public void downloadExcel(HttpServletRequest request, HttpServletResponse response,ProjectStaticManagePageSearcher seacher) {

List<ProjectInfo> data = projectStaticInfoDao.getExcelData(seacher);

String[] title = { "项目编号", "项目名称", "开工日期", "状态"};

HSSFWorkbook workbook = new HSSFWorkbook();

HSSFCellStyle cellStyle = workbook.createCellStyle();

cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);

String filename = "项目信息表.xls";

response.setContentType("application/vnd.ms-excel");

try {

response.setHeader( "Content-Disposition", "attachment;filename=" + new String( filename.getBytes("GB2312"), "ISO-8859-1" ) );

} catch (UnsupportedEncodingException e1) {

// TODO Auto-generated catch block

e1.printStackTrace();

}

//response.setHeader("Content-disposition", "attachment;filename=" + filename);

HSSFSheet sheet = workbook.createSheet(filename);

HSSFRow row = sheet.createRow(0);

HSSFCell cell = null;

int i = 0;

for (; i < title.length; i++) {

cell = row.createCell(i);

cell.setCellValue(title[i]);

}

i = 1;

for (ProjectInfo item : data)

{

row = sheet.createRow(i);

cell = row.createCell(0);

cell.setCellValue(item.getProjectCode());

cell = row.createCell(1);

cell.setCellValue(item.getProjectName());

cell = row.createCell(2);

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd ");

if(item.getStartDate() !=null)

{

cell.setCellValue(sdf.format(item.getStartDate()));

} else {

cell.setCellValue(" ");

}

cell = row.createCell(3);

cell.setCellValue(item.getProjectStatus());

i++;

}

sheet.setColumnWidth(0, (short) 250 * 30);

sheet.setColumnWidth(1, (short) 250 * 40);

sheet.setColumnWidth(2, (short) 250 * 15);

try {

ServletOutputStream stream = response.getOutputStream();

workbook.write(stream);

stream.close();

} catch (IOException e) {

e.printStackTrace();

}

六、分别在dao，mapper，service中写上相应代码mapper中用分页查询的就可以

七、在需要导出的jsp页面写

$("#export").click(

function(){

$("#pageForm").attr('action',"${ctx}/Controller/exportprojectBasicInfo");

$("#pageForm").submit();

$("#pageForm").attr('action',"${ctx}/Controller/list");} );

导出按钮那里用id=” export”触发

弹框：

1按钮

2弹框代码（放在<form:from>之后）

</div>

3js代码

$(function() {

$("#invoice_ajaxload").on("hidden.bs.modal", function(e) {

$(this).removeData();

})

});

3/**

* 跳转到更多操作显示页面

* @return

@RequestMapping("jumpMoreAction/ajaxLoad")

public ModelAndView jumpMoreAction(HttpServletRequest request, String bidCode){

System.out.println(bidCode);

return new ModelAndView("projectInfoManage/moreAction_manage")

.addObject("bidCode", bidCode);}

正则表达式校验姓名

/* 姓名的校验 */

function checkcontact()

{

var checkContact= document.getElementById("contact");

var contactValue=$(".contact").val();

$(".contact").each(function(){

if($(this).val() != "") {

if (!iscontact(contactValue))

{

alert("请输入汉字或者字母!");

document.getElementById("contact").value = "";

throw SyntaxError();

}

});

return true;

}

function iscontact(str){

var reg = /^[a-zA-Z\u4e00-\u9fa5\s]{1,20}$/;

return reg.test(str);

}

用onchange触发

Ajax校验唯一性

一、前台

$("#custName").change(function check() {

var custName = $("#custName").val();

var name = '${name}';

if (name == custName) {

$("#custName").val(name);

} else {

$.ajax({

type : 'post',

url : '${ctx}/SaleCustomorController/ajax/checkcustName',

dataType : 'json',

data : {

custName : custName

success : function(data) {

if (data.info == "repeat") {

alert("已存在客户名称！请重新填写！");

$("#custName").val("");

$("#custName").select();

}

})

}

});

</script>

custName是id里的

二、后台(走一个查询需校验的内容方法)

/**

* 查重客户名称

@RequestMapping(value="ajax/checkcustName",method = { RequestMethod.GET, RequestMethod.POST })

public void checkcustName(HttpServletResponse response,String custName){

Map<String, Object> map = new HashMap<String, Object>();

List<String> name = scManager.searchcustName();

String msg = "unrepeat";

for (int i = 0; i < name.size(); i++) {

if(custName!=null){

//如果存在，直接跳出循环，不再执行，减少时间

if(custName.contentEquals(name.get(i))){

msg = "repeat";

break;}}}ResponseUtil.renderJsonResult(response, new JsonResult(true, msg));}

sql中修改一个表数据另一个表数据同步更新

update 表一，表二 set 同步的数据(如sale_contact_costomor.contact_company = sale_customor.cust_name,)

where 两个表关联的数据

模糊查询

Sql语句加上<if test="custName != null" >

and cust_name like CONCAT('%',#{custName},'%')

</if>

查询角色

//查询登录人的id

id = getCurrentSessionObject().getUser().getId();

List<ServantRole> list = srDao.listRoleByUserId(id);//这是通过id查出来的list

//定义变量

String isHaveRole = "F";

for (ServantRole servantRole : list) {

if("销售leader".equals(servantRole.getDescription())

|| "销售Owner".equals(servantRole.getDescription())){

isHaveRole = "T";

break;

}

前台传后台中文出现乱码问题

中文 = new String(request.getParameter("中文").getBytes("ISO-8859-1"),

"utf-8");

可下拉可输入的输入框及内容拼接

<form:input cssClass="form-control" placeholder="请下拉选择或按照下拉格式输入" list="url_list" path="projectName" id="projectName" maxlength="60"/>

<c:forEach items="${project}" var="list">

</c:forEach>

</datalist>

再输入框中填入日历

一、哪个jsp需要写入日历就在这个jsp引入的model中写入并填充get，set方法

private String startQueryDate;

private String endQueryDate;

代表输入框中的起止时间，在jsp页面中<from:from>下面填入

<form:hidden path="startQueryDate" id="startQueryDate"/>

<form:hidden path="endQueryDate" id="endQueryDate"/>

代表再输入狂显示出时间，接着再写

<%-- <input class="form-control" value="${tQuitRecordPageSearcher.effectDate }" placeholder="离职日期"

onfocus="WdatePicker({isShowWeek:true})" name="effectDate"> --%>

<div id="reportrange"

style="font-size: 12px; background: #fff; cursor: pointer; padding: 3px 8px;

border: 1px solid #e7e7eb;">

</span> <b class="caret"> </b>

</div>

</div>

最后在js里面写，日历完成

$(function () {

var startQueryDate = $("#startQueryDate").val();

if (startQueryDate != "") {

daterangepicker_optionSet.startDate=startQueryDate;

daterangepicker_optionSet.endDate=$("#endQueryDate").val();

}

var cb = function(start, end, label) {

$('#reportrange span').html(start.format('YYYY-MM-DD') + ' - '+ end.format('YYYY-MM-DD'));

}

$('#reportrange span').html(daterangepicker_optionSet.startDate + ' - '+daterangepicker_optionSet.endDate);

$('#reportrange').daterangepicker(daterangepicker_optionSet, cb);

$('#reportrange').on('apply.daterangepicker',function(ev, picker) {

// 在这里进行业务查询操作

$("#startQueryDate").val(picker.startDate.format('YYYY-MM-DD'));

$("#endQueryDate").val(picker.endDate.format('YYYY-MM-DD'));

$("#pageNo").val(1);

$("#pageForm").submit();

});

$("#query").click(function () {

$("#pageNo").val(1);

$("#pageForm").submit();

});

$("#reset").click(function () {

$("input").val('');

$("select").val("-1");

})

});

在输入框显示时间(2)

在jsp页面写入

<input class="form-control" name="proposedDate" id="proposedDate" value="<fmt:formatDate value='${tAppointManagerRecord.proposedDate}'

pattern="yyyy-MM-dd"/>" onfocus="WdatePicker({isShowWeek:true})" />

</div>

完成。

初步接触Java遇到的问题

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