java如何使用JasperReports为单个报表传递多个结果集？

Question

在我的报告中，我有一组字段和两个数据集。我想一次执行三个过程来运行报告。第一个过程用于执行字段集，其余两个过程用于数据集。我通过一个结果集来执行一个工作正常的报告。但是我想从execute（）和port（）方法中再传递两个resultset。是否可以使用JResultSetDataSource或任何其他选项传递多个resultset

public ResultSet execute() throws ClassNotFoundException {
    Statement stmt;
    ResultSet resultset = null;
    Connection con = null;
    try {
        String selectstatement = "CALL P_Select_Salary2 ('2013-01-01', '2013-01-31', 1, 'Salary_OA')";
        Class.forName("com.mysql.jdbc.Driver");
        con = DriverManager.getConnection("jdbc:mysql://localhost:3306/compliance?user=root&password=root");
        stmt = con.createStatement();
        resultset = stmt.executeQuery(selectstatement);

    } catch (SQLException e) {
        e.printStackTrace();
    } finally {
        close(con);
        close(resultset);
    }
    return resultset;
}

public ResultSet port() throws ClassNotFoundException {
    Statement stmt;
    ResultSet resultset = null;
    Connection con = null;
    try {
        String selectstatement = "CALL P_Select_Salary3 ('2013-01-01', '2013-01-31', 1, 'Salary')";
        Class.forName("com.mysql.jdbc.Driver");
        con = DriverManager.getConnection("jdbc:mysql://localhost:3306/compliance?user=root&password=root");
        stmt = con.createStatement();
        resultset = stmt.executeQuery(selectstatement);

    } catch (SQLException e) {
        e.printStackTrace();
    } finally {
        close(con);
        close(resultset);
    }
    return resultset;
}

public void generateReport() {
    Connection connection = null;
    Statement stmt;
    ResultSet resultset = null;
    try {
        String selectstatement = "CALL P_Select_Salary ('2013-01-01', '2013-02-28', 1, 'Salary_Summary')";
        Class.forName("com.mysql.jdbc.Driver");
        connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/compliance?user=root&password=root");
        stmt = connection.createStatement();
        resultset = stmt.executeQuery(selectstatement);
        JRResultSetDataSource resultsetdatasource = new JRResultSetDataSource(resultset);
        String realpath = FacesContext.getCurrentInstance().getExternalContext().getRealPath("common/reports/wageslip.jasper");
        jasperprint = JasperFillManager.fillReport(realpath, new HashMap(), resultsetdatasource);
        HttpServletResponse httpservlet = (HttpServletResponse) FacesContext.getCurrentInstance().getExternalContext().getResponse();
        httpservlet.addHeader("Content-disposition", "attachment;filename=wageslip.pdf");
        ServletOutputStream servletout = httpservlet.getOutputStream();
        JasperExportManager.exportReportToPdfStream(jasperprint, servletout);
        FacesContext.getCurrentInstance().responseComplete();
    } catch (net.sf.jasperreports.engine.JRException JRexception) {
        logger.info("JRException Exception" + JRexception.getMessage());
        JsfUtil.addErrorMessage("No Datas between FromDate and ToDate");
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        close(connection);
        close(resultset);
    }
}

Answer 1

可以在参数映射中发送任意多个结果集

Map reportParams = new HashMap(); reportParams.put("ds1", new JRBeanCollectionDataSource(beanCollection1)); reportParams.put("ds2", new JRBeanCollectionDataSource(beanCollection2));

JasperPrint jrprint = JasperFillManager.fillReport(jasperReport,reportParams, new JREmptyDataSource());

确保在报告中使用相同的名称（ds1、ds2）声明参数，并将ParameterClass设置为

net.sf.jasperreports.engine.data.JRBeanCollectionDataSource

现在可以用$p{ds1}、$p{ds2}等来检索它们。 您还没有指定需要它们做什么，但实际上可以使用这些参数做任何事情，比如设置其中一个参数或表的数据源等

评论后编辑：

我有一个列表组件，我将其设置为Connection/Datasource Expression=$P{list1}， 其中，$P{list1}是net.sf.jasperreports.engine.JRResultSetDataSource类型的参数

我的列表组件如下所示：

<jr:list xmlns:jr="http://jasperreports.sourceforge.net/jasperreports/components" xsi:schemaLocation="http://jasperreports.sourceforge.net/jasperreports/components http://jasperreports.sourceforge.net/xsd/components.xsd" printOrder="Vertical">
                    <datasetRun subDataset="dataset1">
                        <dataSourceExpression><![CDATA[$P{ds1}]]></dataSourceExpression>
                    </datasetRun>
                    <jr:listContents height="66" width="400">
                        <textField>
                            <reportElement x="10" y="10" width="100" height="20"/>
                            <textElement/>
                            <textFieldExpression><![CDATA[$F{empname}]]></textFieldExpression>
                        </textField>
                    </jr:listContents>
                </jr:list>

如你所见，我有元素 Dataset1是添加列表组件时自动添加到报表中的数据集（如果使用iReport进行设计）。 现在，在dataset1下（正如我所说，它是一个子数据集，所以它允许参数、字段和变量），我声明字段：

<subDataset name="dataset1">
        <field name="empno" class="java.lang.Integer"/>
        <field name="empname" class="java.lang.String"/>
    </subDataset>

就这样。我已经尝试过这个确切的代码，对我有效