来自SQL数据库的带有时间的JFreechart图表 [英] JFreechart chart with Time from SQL Database
问题描述
我是JFreeChart的新手，我正在尝试创建一个图表，该图表在y轴上显示一个值，在x轴上显示时间. 所有这些数据(值和时间)已经在我的数据库中，并且每3到4秒就有一个类似的值.
但是，我不想显示所有内容或保持动态.我只想显示一个图表，例如显示从2020-06-16 10:31:52到2020-06-29 11:31:52的所有值(但正如我所说的，所有内容已经在我的数据库中). /p>
这是我的变化形式(不包括所有进口商品):
public class JDBCTest {
private void display() {
JFrame f = new JFrame("JDBCTest");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JDBCXYDataset jds = createDataset();
JFreeChart chart = ChartFactory.createTimeSeriesChart(
"Inventory", "Date", "Count", jds, true, true, false);
f.add(new ChartPanel(chart));
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
private JDBCXYDataset createDataset() {
try {
Connection conn = DriverManager.getConnection(
"jdbc:mysql://localhost:","", "");
Statement st = conn.createStatement();
st.execute("DROP TABLE IF EXISTS Test ");
st.execute("create table Test(Date_Heure timestamp, PV float)");
String Date_Debut = "2020-06-25 13:28:08";
String Date_Fin = "2020-06-26 13:28:08";
String sql1 = "INSERT INTO Test (Date_Heure,PV) "
+ "SELECT TABLE ,TABLE "
+ "FROM TABLE "
+ "WHERE Date_Heure BETWEEN ? AND ?";
PreparedStatement ps = conn.prepareStatement(sql1);
ps.setString(1,Date_Debut);
ps.setString(2,Date_Fin);
ps.executeUpdate();
JDBCXYDataset jds = new JDBCXYDataset(conn);
jds.executeQuery("select TABLE , TABLE from Test");
return jds;
} catch (SQLException ex) {
ex.printStackTrace(System.err);
}
return null;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new JDBCTest().display();
}
});
}
}
错误是从数据库而不是代码本身发出的.
该代码的灵感来自垃圾桶的工作 http://stackoverflow.com/a/24762078/230513
其他信息:
Date_Time类型的timestamp
PV类型的float
使用问题.使用JDBCCategoryDataset，第一列将是类别名称，[其余]列将[是]值(每个列代表一个序列)；"；使用JDBCXYDataset，第一列将是x轴，其余列是y轴值. "结果，我希望您的查询是这样的:
SELECT Date_Time, PV …
由于您的域轴是时间，请考虑旋转标签位置，如此处所示.在决定时，请注意TimeSeries在方向上不太灵活，但在格式上更灵活.
我数据库中的值是
Float.
对示例的以下更改说明了使用浮点值.请注意，PV的类型为float，而PreparedStatement使用的是setFloat().
JDBCCategoryDataset jds = createDataset();
JFreeChart chart = ChartFactory.createLineChart("Test", "Time", "PV",
jds,PlotOrientation.VERTICAL, true, true, false);
CategoryPlot plot = (CategoryPlot) chart.getPlot();
CategoryAxis domain = plot.getDomainAxis();
plot.getDomainAxis().setCategoryLabelPositions(CategoryLabelPositions.UP_45);
…
private JDBCCategoryDataset createDataset() {
try {
Connection conn = DriverManager.getConnection(
"jdbc:h2:mem:test", "", "");
Statement st = conn.createStatement();
st.execute("create table data(when timestamp, pv float)");
PreparedStatement ps = conn.prepareStatement(
"insert into data values (?, ?)");
Calendar c = Calendar.getInstance();
for (int i = 0; i < N; i++) {
ps.setTimestamp(1, new Timestamp(c.getTimeInMillis()));
ps.setFloat(2, (float)r.nextGaussian() + 2);
ps.execute();
c.add(Calendar.SECOND, r.nextInt(60 * 60));
}
JDBCCategoryDataset jds = new JDBCCategoryDataset(conn);
jds.executeQuery("select when, pv from data");
return jds;
} catch (SQLException ex) {
ex.printStackTrace(System.err);
}
return null;
}
I'm new with JFreeChart and I'm trying to create a chart that display a value on the y-axis and the time on the x-axis. All theses data (value and time) are already in my database and I have something like a value for each 3 to 4 seconds.
However I do not want to display everything or to be dynamic. I just want to display a chart that shows all the values from 2020-06-16 10:31:52 to 2020-06-29 11:31:52 for example (but everything is already in my Database as I said).
Here is my variation of this (without all the imports) :
public class JDBCTest {
private void display() {
JFrame f = new JFrame("JDBCTest");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JDBCXYDataset jds = createDataset();
JFreeChart chart = ChartFactory.createTimeSeriesChart(
"Inventory", "Date", "Count", jds, true, true, false);
f.add(new ChartPanel(chart));
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
private JDBCXYDataset createDataset() {
try {
Connection conn = DriverManager.getConnection(
"jdbc:mysql://localhost:","", "");
Statement st = conn.createStatement();
st.execute("DROP TABLE IF EXISTS Test ");
st.execute("create table Test(Date_Heure timestamp, PV float)");
String Date_Debut = "2020-06-25 13:28:08";
String Date_Fin = "2020-06-26 13:28:08";
String sql1 = "INSERT INTO Test (Date_Heure,PV) "
+ "SELECT TABLE ,TABLE "
+ "FROM TABLE "
+ "WHERE Date_Heure BETWEEN ? AND ?";
PreparedStatement ps = conn.prepareStatement(sql1);
ps.setString(1,Date_Debut);
ps.setString(2,Date_Fin);
ps.executeUpdate();
JDBCXYDataset jds = new JDBCXYDataset(conn);
jds.executeQuery("select TABLE , TABLE from Test");
return jds;
} catch (SQLException ex) {
ex.printStackTrace(System.err);
}
return null;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new JDBCTest().display();
}
});
}
}
EDIT : The error was comming from the Database and not from the code itself.
Edit : The code is inspired around trashgod's work http://stackoverflow.com/a/24762078/230513
additional information :
Date_Time type's timestamp
PV type's float
The example cited using JDBCXYDataset also works with JDBCCategoryDataset, as shown below and in your original question. Using JDBCCategoryDataset, "The first column will be the category name and [the] remaining columns [will be] values (each column represents a series);" using JDBCXYDataset, "The first column will be the x-axis and remaining columns y-axis values. " As a result, I would expect your query to be something like this:
SELECT Date_Time, PV …
As your domain axis is time, consider rotating the label positions, as shown here. When deciding, note that a TimeSeries is less flexible about orientation but more flexible about formatting.
the values in my database are
Float.
The following changes to the example illustrate using floating point values. Note that PV is of type float, and the PreparedStatement uses setFloat().
JDBCCategoryDataset jds = createDataset();
JFreeChart chart = ChartFactory.createLineChart("Test", "Time", "PV",
jds,PlotOrientation.VERTICAL, true, true, false);
CategoryPlot plot = (CategoryPlot) chart.getPlot();
CategoryAxis domain = plot.getDomainAxis();
plot.getDomainAxis().setCategoryLabelPositions(CategoryLabelPositions.UP_45);
…
private JDBCCategoryDataset createDataset() {
try {
Connection conn = DriverManager.getConnection(
"jdbc:h2:mem:test", "", "");
Statement st = conn.createStatement();
st.execute("create table data(when timestamp, pv float)");
PreparedStatement ps = conn.prepareStatement(
"insert into data values (?, ?)");
Calendar c = Calendar.getInstance();
for (int i = 0; i < N; i++) {
ps.setTimestamp(1, new Timestamp(c.getTimeInMillis()));
ps.setFloat(2, (float)r.nextGaussian() + 2);
ps.execute();
c.add(Calendar.SECOND, r.nextInt(60 * 60));
}
JDBCCategoryDataset jds = new JDBCCategoryDataset(conn);
jds.executeQuery("select when, pv from data");
return jds;
} catch (SQLException ex) {
ex.printStackTrace(System.err);
}
return null;
}
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