Hbase期末小项目，结合之前学习的Java基础；通过API对Hbase *** 作，结合JAVAWeb将结果展示于页面上，通过页面按钮实现增删改查功能。
项目用到的技术1.Hbase基础知识，增删改查，以及API *** 作
2.JAVAWeb基础知识，了解前后端数据如何传输，何种形式
3.一定的HTML前端基础和Javascript基础
4.AJAX前后端数据交互
项目目录结构hbase里面包括Hbase的工具类HbseUtil以及实体类HbaseDemo
具体实现过程 Hbase *** 作 Hbase表结构后端java代码
// 添加数据
public void add(String rowkey, String name, String type, String place, String price, String weight) throws Exception {
//调用HbaseUtil工具类
boolean r1=HbaseUtil.Insert_Data(tablename,rowkey,"info1","name",name);
boolean r2=HbaseUtil.Insert_Data(tablename,rowkey,"info1","type",type);
boolean r3=HbaseUtil.Insert_Data(tablename,rowkey,"info2","place",place);
boolean r4=HbaseUtil.Insert_Data(tablename,rowkey,"info2","price",price);
boolean r5=HbaseUtil.Insert_Data(tablename,rowkey,"info2","weight",weight);
if(r1&&r2&&r3&r4&r5){
System.out.println("添加成功！");
}
else{
System.out.println("添加失败");
}
}
Hbase实现删除功能
后端Java代码
//删除整行数据
public void delete_all(String rowkey) throws IOException {
boolean r = HbaseUtil.Exec_DelData(tablename,rowkey);
}
// 删除一行数据的某列，如name列等
public void delete_column(String rowkey, String column) throws IOException {
if (column.equals("name") || column.equals("type")){
boolean r = HbaseUtil.Exec_DelData(tablename, rowkey, "info1",column);
}
if (column.equals("place") || column.equals("price") || column.equals("weight")){
boolean r2 = HbaseUtil.Exec_DelData(tablename, rowkey,"info2",column);
}
}
Hbase实现修改功能
Hbase修改可以直接调用增加函数，产生新的时间戳，相当于修改
Hbase实现查询功能主要应用Hbase的过滤器实现各种查询
比如查询行键以XXX开头的数据
// 查询行键以**开头数据 public Listget_byrowkey1(String str) throws IOException { //创建scan扫描对象 Scan scan = new Scan(); //设置过滤器 Filter filter = new RowFilter(CompareFilter.CompareOp.EQUAL, new BinaryPrefixComparator(Bytes.toBytes(str))); //为scan对象设置过滤器 scan.setFilter(filter); //表对象实列化 Table table=HbaseUtil.GetConnection().getTable(TableName.valueOf(tablename)); //结果集 ResultScanner results=table.getScanner(scan); //查询到的数据不止一个，存放到列表中 List mylist = new ArrayList<>(); for (Result result : results){ Cell[] cells = result.rawCells(); //将结果转换为JSON格式，方面后续javaweb *** 作 JSONObject object = new JSONObject(); for (Cell cell : cells){ object.put(Bytes.toString(CellUtil.cloneQualifier(cell)),Bytes.toString(CellUtil.clonevalue(cell))); object.put("rowkey",Bytes.toString(CellUtil.cloneRow(cell))); } mylist.add(object); } return mylist; }
多个过滤器结合查询
如查询姓名是XXX，产地为XXX的数据
// 查询name为XXX，产地为XXX数据
public List select_two(String value1, String value2) throws IOException {
Scan scan = new Scan();
SingleColumnValueFilter singleColumnValueFilter1 = new SingleColumnValueFilter(Bytes.toBytes("info1"), Bytes.toBytes("name"), CompareFilter.CompareOp.EQUAL, new BinaryComparator(Bytes.toBytes(value1)));
SingleColumnValueFilter singleColumnValueFilter2 = new SingleColumnValueFilter(Bytes.toBytes("info2"), Bytes.toBytes("place"), CompareFilter.CompareOp.EQUAL, new BinaryComparator(Bytes.toBytes(value2)));
ArrayList filters = new ArrayList<>();
filters.add(singleColumnValueFilter1);
filters.add(singleColumnValueFilter2);
// 多个过滤器用集合存放
// And关系MUST_PASS_ALL OR关系MUST_PASS_ONE
Filter filterList = new FilterList(FilterList.Operator.MUST_PASS_ALL,filters);
// 为scan设置过滤器
scan.setFilter(filterList);
Table table=HbaseUtil.GetConnection().getTable(TableName.valueOf(tablename));
ResultScanner results=table.getScanner(scan);
List mylist = new ArrayList<>();
for (Result result : results){
Cell[] cells = result.rawCells();
JSONObject object = new JSONObject();
for (Cell cell : cells){
object.put(Bytes.toString(CellUtil.cloneQualifier(cell)),Bytes.toString(CellUtil.clonevalue(cell)));
object.put("rowkey",Bytes.toString(CellUtil.cloneRow(cell)));
}
mylist.add(object);
}
return mylist;
}
其他查询用过滤器均可实现，将数据结果转换为JSON格式，方面后端数据通过AJAX传输
Serverlet *** 作 增加功能//前后端交互的路径
@WebServlet("/add")
public class AddServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// 接收前端发送过来的数据，获取请求体数据
BufferedReader reader = req.getReader();
// 读一行，只有一行
String params = reader.readLine();
// JSON字符串转java对象(JSONObject对象)
JSONObject object = JSON.parseObject(params);
String rowkey = object.getString("rowkey");
String name = object.getString("name");
String type = object.getString("type");
String place = object.getString("place");
String price = object.getString("price");
String weight = object.getString("weight");
// 实现HbaseDemo实体类 *** 作Hbase数据库
HbaseDemo hbaseDemo = new HbaseDemo();
try {
hbaseDemo.add(rowkey,name,type,place,price,weight);
// 响应成功标识
resp.getWriter().write("success");
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//执行post请求时也调用doGet方法
this.doGet(req,resp);
}
}
前端HTML页面
Title
删除功能
（删除整行）
@WebServlet("/delete_all")
public class DeleteAllServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String rowkey = req.getParameter("rowkey");
HbaseDemo hbaseDemo = new HbaseDemo();
hbaseDemo.delete_all(rowkey);
// 请求转发到hbase.html页面,由下一个Servlet完成响应体，当前Servlet可以设置响应头（留头不留体）
req.getRequestDispatcher("/hbase.html").forward(req,resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doGet(req,resp);
}
}
前端HTML页面(全表查询到的数据和删除为同一界面)
删除时前端url直接携带一个参数rowkey，后端接收到rowkey，根据rowkey进行删除
Title
rowkey
name
type
place
price
weight
*** 作
000
000
000
000
000
000
修改 删除全部 删除一列
000
000
000
000
000
000
修改
修改功能
@WebServlet("/selectByrowkey")
public class ChangeServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//接收rowkey，req.getParameter()切割字符串，按照and、=切割
String rowkey = req.getParameter("rowkey");
//调用查询
HbaseDemo hbaseDemo = new HbaseDemo();
JSONObject brand = hbaseDemo.change(rowkey);
// 储存到request域中
req.setAttribute("rowkey",brand.getString("rowkey"));
req.setAttribute("name",brand.getString("name"));
req.setAttribute("type",brand.getString("type"));
req.setAttribute("place",brand.getString("place"));
req.setAttribute("price",brand.getString("price"));
req.setAttribute("weight",brand.getString("weight"));
// 转发到change.jsp
req.getRequestDispatcher("/change.jsp").forward(req,resp);
// 响应成功标识
resp.getWriter().write("success");
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doGet(req,resp);
}
}
前端JSP页面（需要改进的地方，没有用HTML页面实现）
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%--加上这句才能获得request域中数据--%>
<%@page isELIgnored="false" %>
修改信息
修改信息
查询功能
查询行键是XXX开头的数据
@WebServlet("/get_byrowkey1")
public class Get_byrowkey1Servlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
BufferedReader reader = req.getReader();
String params = reader.readLine();
JSONObject object = JSON.parseObject(params);
String str = object.getString("rowkey1");
HbaseDemo hbaseDemo = new HbaseDemo();
List mylist = hbaseDemo.get_byrowkey1(str);
String jsonString = JSON.toJSONString(mylist);
resp.setContentType("text/json;charset=utf-8");
resp.getWriter().write(jsonString);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doGet(req,resp);
}
}
前端HTML页面
Title
不足之处
1.修改页面回显数据展示没办法再HTML显示，所以用了JSP页面
2.分页查询时如何将页面的page和Hbase行键联系起来，因为Hbase分页，主要是传入一个起始行键和条数，而前端传输的是page参数，不能和行键联系起来，所以现在分页功能不完善
结果显示
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