In this “Please take a look at this Sample Project.” as mentioned by you earlier , if I provide a string/date value in the code : a blank screen with no data comes . Data only in double format is picking up to render the chart which is not proper. String sql = ” SELECT * from Fan2TempMotorBearing where rownum < 50 order by datetime”; Statement stmt = conn.createStatement(); ResultSet rset = stmt.executeQuery(sql);
while (rset.next()) { Date xVal =rset.getDate(“datetime”);// Date values double y1Val = (double)rset.getDouble(“y_actual”), y2Val = (double)rset.getDouble(“y_predicted”);
map = new HashMap<Object,Object>(); map.put(“x”, xVal); map.put(“y”, y1Val); list1.add(map); dataPoints1 = gsonObj.toJson(list1);
map = new HashMap<Object,Object>(); map.put(“x”, xVal); map.put(“y”, y2Val); list2.add(map); dataPoints2 = gsonObj.toJson(list2); } }
Query: create table Fan2TempMotorBearing (datetime date , y_actual float(50), y_predicted float(50)) insert into Fan2TempMotorBearing values (TO_DATE(‘2018-07-01 00-00-00′,’yyyy-mm-dd hh24-mi-ss’),’50.183′,’53.0519169458035′) insert into Fan2TempMotorBearing values (TO_DATE(‘2018-07-01 00-05-00′,’yyyy-mm-dd hh24-mi-ss’),’50.183′,’53.0261445540871′)
kindly check for this if possible why only double parameters can plot the graph from database and not string / date type data.
dear indranil
Do you have a sample project with datetime picker attached to it. I have checked this sample but the issue is that it fetches data only for double values. if my x axis has string values or datetime values it does not produce the required output but gives a blank screen.
This is not giving the desired output.
I have mailed you already with my issue Manoj. Was not able to post the code here so pasted in jsfiddle.
<%@ page import="java.util.*" %> <%@ page import="java.sql.*" %> <%@ page import="java.math.*" %> <%@ page import="com.google.gson.Gson"%> <% Gson gsonObj = new Gson(); Map<Object,Object> map = null; List<Map<Object,Object>> list1 = new ArrayList<Map<Object,Object>>(), list2 = new ArrayList<Map<Object,Object>>(); String dataPoints1 = null, dataPoints2 = null; /* https://www.tutorialspoint.com/jdbc/jdbc-db-connections */ try { Class.forName("oracle.jdbc.driver.OracleDriver").newInstance(); } catch(Exception ex) { System.out.println("Error!"); System.exit(1); } String url = "jdbc:oracle:thin:@localhost:1521:xe"; String user = "SYS as SYSDBA"; String PASS = "SYS"; Connection conn = DriverManager.getConnection(url, user, PASS); PreparedStatement pstmt = null; try { String sql = "select * from shv order by datetime "; Statement stmt = conn.createStatement(); ResultSet rset = stmt.executeQuery(sql); while (rset.next()) { String xVal = rset.getString("datetime"); String y1Val = (String)rset.getString("y_actual"); String y2Val = rset.getString("y_predicted"); map = new HashMap<Object,Object>(); map.put("x", xVal); map.put("y", y1Val); list1.add(map); dataPoints1 = gsonObj.toJson(list1); //Date dt=new Date(dataPoints1); map = new HashMap<Object,Object>(); map.put("x", xVal); map.put("y", y2Val); list2.add(map); dataPoints2 = gsonObj.toJson(list2); } } catch (SQLException e) { System.out.println(e); } %> <!DOCTYPE HTML> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <script src="https://cdn.canvasjs.com/canvasjs.min.js"></script> <script type="text/javascript"> window.onload = function(){ var chart = new CanvasJS.Chart("chartContainer", { theme: "light2", animationEnabled: true, title: { text: "Multiseries line Chart with Data from Oracle Database" }, data: [{ type: "line", //change type to bar, line, area, pie, etc dataPoints: <%out.print(dataPoints1);%> },{ type: "line", //change type to bar, line, area, pie, etc dataPoints: <%out.print(dataPoints2);%> }] }); chart.render(); function toogleDataSeries(e){ if (typeof(e.dataSeries.visible) === "undefined" || e.dataSeries.visible) { e.dataSeries.visible = false; } else{ e.dataSeries.visible = true; } chart.render(); } } </script> </head> <body> <div id="chartContainer" style="width: 100%; height: 400px"></div> </body> </html>
https://jsfiddle.net/munmunpanda/82Luwp9z/3/
This is a jsfiddle link where in html i have placed my entire code and in javascript section i have placed the queries that i m running currently.
As per your instructions i ran the sample project but got a blank screen . kindly reply soon.
hi manoj
i want to create using java by using hashmap or arraylist a multiseries chart from data from database . oracle database.