jasper 使用，关于list的连续模板读取，读取不同模板

1.关于list的使用

定义一个dataset，定义list的字段

new net.sf.jasperreports.engine.data.JRBeanCollectionDataSource($F{mcLableDetailList})

 

这样就不用搞复杂的子父报表

2.连续读取不同的模板：

使用java代码实现：根据条件区分读取不同代码

// controller
    @GetMapping(value = { "printPalletLable" })
    public void printPalletLable(HttpServletResponse response) {
        try {
            List<LableVo> lableVoList;
            Map map = warpUsualParameters(super.getRequestParameters());

            lableVoList = relInvoiceService.printPalletLable(map);
            if (CollectionUtils.isEmpty(lableVoList)) {
                return;
            }
            List<LableVo> mcList = new ArrayList<>();
            List<LableVo> mxList = new ArrayList<>();
            List<JasperPrint> jasperPrintList = new ArrayList<>();
            Map<String, Object> params = new HashMap<>();
            String path = new ClassPathResource("reports/logs/anji.png").getPath();
            params.put("imageURL",path);
            lableVoList.stream().forEach(lableVo -> {
                if ("MC".equals(lableVo.getTarget())) {
                    mcList.add(lableVo);
                } else {
                    mxList.add(lableVo);
                }
            });
            if (CollectionUtils.isNotEmpty(mxList)) {
                InputStream inputStream = new ClassPathResource("reports/mxLable.jasper").getInputStream();
                JasperPrint print = JasperPrinter.fillReport(inputStream, params, mxList);
                jasperPrintList.add(print);
            }
            if (CollectionUtils.isNotEmpty(mcList)) {
                InputStream inputStream2 = new ClassPathResource("reports/mcLable.jasper").getInputStream();
                JasperPrint print2 = JasperPrinter.fillReport(inputStream2, params, mcList);
                jasperPrintList.add(print2);
            }
            JasperPrinter.exportPDFToWebList(jasperPrintList, null, response);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
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//JasperPrinter 类
import net.sf.jasperreports.engine.*;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;
import net.sf.jasperreports.engine.export.JRPdfExporter;
import net.sf.jasperreports.export.SimpleExporterInput;
import net.sf.jasperreports.export.SimpleOutputStreamExporterOutput;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Collection;
import java.util.List;
import java.util.Map;

/**
 * @ClassName JasperPrinter
 * @Description: TODO
 * @Author dingkaiqiang
 * @Date 2019-11-28
 * @Version V1.0
 **/
public class JasperPrinter {
    public static void exportPDFToWeb(JasperPrint jasperPrint, String outputFileName, HttpServletResponse response)
            throws JRException, IOException {
        response.setContentType("application/pdf");
        JasperExportManager.exportReportToPdfStream(jasperPrint, response.getOutputStream());
    }

    public static JasperPrint fillReport(InputStream inputStream, Map<String, Object> params, Collection<?> detailList)
            throws JRException {
        JasperPrint jasperPrint = null;
        JRBeanCollectionDataSource datasource = null;
        if (detailList != null && !detailList.isEmpty()) {
            datasource = new JRBeanCollectionDataSource(detailList);
            jasperPrint = JasperFillManager.fillReport(inputStream, params, datasource);
        } else {
            jasperPrint = JasperFillManager.fillReport(inputStream, params, new JREmptyDataSource());
        }
        return jasperPrint;
    }
    /**
     * 连续读取多个模板
     * @param jasperPrintList
     * @param outputFileName
     * @param response
     * @throws JRException
     * @throws IOException
     */
    public static void exportPDFToWebList(List<JasperPrint> jasperPrintList, String outputFileName, HttpServletResponse response)
            throws JRException, IOException{
        ServletOutputStream outputStream = response.getOutputStream();
        try {
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            JRPdfExporter exporter = new JRPdfExporter();
            exporter.setExporterInput(SimpleExporterInput.getInstance(jasperPrintList));
            exporter.setExporterOutput(new SimpleOutputStreamExporterOutput(baos));
            exporter.exportReport();
            byte[] bytes = baos.toByteArray();
            // 写出文件的类型
            response.setContentType("application/pdf;charset=UTF-8");
            baos.close();
            outputStream.write(bytes);
        } finally {
            outputStream.flush();
        }


    }
}