JasperReports导出图片时报数组越界

前段时间对JasperReports使用的比较熟了，可是今天为了省事（仅用于调试代码），做了下图所示的报表：

然后Junit测试的时候报以下异常：

java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
	at java.util.ArrayList.RangeCheck(ArrayList.java:547)
	at java.util.ArrayList.get(ArrayList.java:322)
	at java.util.Collections$SynchronizedList.get(Collections.java:1820)
	at net.sf.jasperreports.engine.export.JRGraphics2DExporter.exportReportToGraphics2D(JRGraphics2DExporter.java:245)
	at net.sf.jasperreports.engine.export.JRGraphics2DExporter.exportReport(JRGraphics2DExporter.java:184)
	at grp.pt.pb.ss.bs.CreateEvocherImageService.generateJpeg(CreateEvocherImageService.java:266)
           

而且用IReport预览也不显示任何信息。我先是取看看源码，注意到有个pages信息，于是我想是不是与分页相关。

public void exportReportToGraphics2D() throws JRException
	{
		grx.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
		//grx.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_OFF);
		grx.setRenderingHint(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_ON);
		grx.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BICUBIC);

		AffineTransform atrans = new AffineTransform();
		atrans.translate(globalOffsetX, globalOffsetY);
		atrans.scale(zoom, zoom);
		grx.transform(atrans);

		List<JRPrintPage> pages = jasperPrint.getPages();
		if (pages != null)
		{
			Shape oldClipShape = grx.getClip();
	
			grx.clip(new Rectangle(0, 0, jasperPrint.getPageWidth(), jasperPrint.getPageHeight()));
	
			try
			{
				JRPrintPage page = pages.get(startPageIndex);
				exportPage(page);
			}
			finally
			{
				grx.setClip(oldClipShape);
			}
		}
	}
           

调整报表

这样就可以了，看来detail里面是不能放Parameter类型的参数的。