用JFreeReport做报表实践

准备工作：
下载jfreeReport0.8.7 地址:

使用JFreeReport生成报表通常需要以下三个基本步骤：
A. 生成可通过TableModel接口访问的数据，如本例中的createData方法完成的功能。
B. 生成一个JFreeReport实例，他定义了我们如何格式化显示数据，如本例中的createReportDefinition方法完成的功能。
C. 将数据和JFreeReport实例连接起来，并且将该JFreeReport实例传给PreviewDialog的一个实例显示给用户。

下面开始>>>>>
1. 新建一个WEB工程，在WebRoot\lib中import 如下jar文件:jcommon-1.0.1.jar jfreereport-0.8.7.jar jfreereport-demo-0.8.7.jar jfreereport-servlet-demo-0.8.7.jar
(可在jfreereport包中解压得到)
2. 写一个Demo.java 加入到工程的src包中. 内容如下：

import java.awt.Color;
import java.awt.geom.Point2D;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableModel;

import org.jfree.report.ElementAlignment;
import org.jfree.report.JFreeReport;
import org.jfree.report.JFreeReportBoot;
import org.jfree.report.ReportProcessingException;
import org.jfree.report.demo.helper.DefaultCloseHandler;
import org.jfree.report.demo.helper.DemoHandler;
import org.jfree.report.demo.helper.PreviewHandler;
import org.jfree.report.elementfactory.TextFieldElementFactory;
import org.jfree.report.modules.gui.base.PreviewDialog;
import org.jfree.ui.FloatDimension;
import org.jfree.util.Log;
public class Demo implements DemoHandler
{
   private class HelloWorldPreviewHandler implements PreviewHandler
{
    public HelloWorldPreviewHandler()
    {
    }

    public void attemptPreview()
    {
      executeReport();
    }
}

public Demo (){
}

protected void executeReport ()
{
    final TableModel data = createData();
    final JFreeReport report = createReportDefinition();
    report.setData(data);
    try
    {
      final PreviewDialog preview = new PreviewDialog(report);
      preview.addWindowListener(new DefaultCloseHandler());
      preview.pack();
      preview.setVisible(true);
    }
    catch (ReportProcessingException e)
    {
      Log.error("Failed to generate report ", e);
    }
}
private TableModel createData ()
{

    final Object[] columnNames = new String[]{"Column1", "Column2"};
    final DefaultTableModel result = new DefaultTableModel(columnNames, 101);
    for (int i=1;i<101;i++){
       result.setValueAt("用繁體字寫幾個看看\n", i, 0);
       result.setValueAt("简体中文输出第"+i+"次", i, 1);
    }
    return result;
}
private JFreeReport createReportDefinition ()
{

    final JFreeReport report = new JFreeReport();
    report.setName(getDescription());

    TextFieldElementFactory factory = new TextFieldElementFactory();
    factory.setName("T1");
    factory.setAbsolutePosition(new Point2D.Float(0, 0));
    factory.setMinimumSize(new FloatDimension(150, 12));
    factory.setColor(Color.black);
    factory.setHorizontalAlignment(ElementAlignment.RIGHT);
    factory.setVerticalAlignment(ElementAlignment.MIDDLE);
    factory.setNullString("-");
    factory.setFieldname("Column1");
    report.getItemBand().addElement(factory.createElement());

    factory = new TextFieldElementFactory();
    factory.setName("T2");
    factory.setAbsolutePosition(new Point2D.Float(200, 0));
    factory.setMinimumSize(new FloatDimension(150, 12));
    factory.setColor(Color.black);
    factory.setHorizontalAlignment(ElementAlignment.LEFT);
    factory.setVerticalAlignment(ElementAlignment.MIDDLE);
    factory.setNullString("-");
    factory.setFieldname("Column2");
    report.getItemBand().addElement(factory.createElement());
    return report;

}
protected String getDescription ()
{
    return "A Very Simple Report";
}
public String getDemoName()
{
    return "Hello World Demo (External)";
}

public PreviewHandler getPreviewHandler()
{
    return new HelloWorldPreviewHandler();
}
    public static void main (final String[] args)
{
        JFreeReportBoot.getInstance().start();
        new Demo().executeReport();
}
}


3.在eclipse 中运行(Shift+Alt+X J)运行出来了. 仍有错误或警告。下面来消除它们.
4. Exception in thread "export-worker--1" java.lang.NoClassDefFoundError: org/jfree/fonts/registry/FontRecord === 解决办法是 import     libfonts-0.1.4.jar
5. WARN: Unable to initialize the module misc-bsf
org.jfree.base.modules.ModuleInitializeException: Unable to load the bean scripting framework manager class. This class is required to execute the BSFExpressions. === 解决办法是 import bsf-2.3.0.jar
6. WARN: Unable to initialize the module misc-beanshellorg.jfree.base.modules.ModuleInitializeException: Unable to load the bean shell interpreter class. This class is required to execute the BeanShellExpressions.    === 解决办法是 import bsh-1.3.0.jar
7. WARN: Unable to load module classes for parser-simple:org/jfree/xml/parser/AbstractXmlReadHandler
WARN: Unable to load module classes for parser-ext:org/jfree/xml/parser/AbstractXmlReadHandler
=== 解决办法是 import jcommon-xml-1.0.1.jar
8 最终出现：
INFO: Registering fonts for the iText library; using a cached font registry.
INFO: Completed font registration.
INFO: setReport(..): started pagination ...
OK，一切顺利完成.
9. 总之最后的WebRoot\lib中一共引入了
bsf-2.3.0.jar bsh-1.3.0.jar itext-1.3.6.jar jcommon-1.0.1.jar jfreereport-0.8.7.jar jfreereport-demo-0.8.7.jar jfreereport-servlet-demo-0.8.7.jar
libfonts-0.1.4.jar poi-3.0-alpha1-20050704.jar
这些JAR文件.