java后台生成pdf文件 预览/直接下载

import com.itextpdf.text.Document;
import com.itextpdf.text.PageSize;
import com.itextpdf.text.pdf.PdfException;
import com.itextpdf.text.pdf.PdfPageEventHelper;
import com.itextpdf.text.pdf.PdfWriter;
import com.itextpdf.tool.xml.XMLWorkerFontProvider;
import com.itextpdf.tool.xml.XMLWorkerHelper;
import com.jd.jr.risk.common.font.PdfFont;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.*;
import java.nio.charset.Charset;

/**

• pdf的工具类

• @author lichaopu1

• @date 2019-03-26 14:00 2019-03-26 14:24
  */
  public class PdfUtil {

  private static final Logger logger = LoggerFactory.getLogger(PdfUtil.class);

  /**

  • 导出到指定的文件目录中
  • @param htmlContent html格式的文件内容
  • @param filePath 导出的目标路径
  • @throws PdfException
    */
    public static void exportToFile(String htmlContent, String filePath) throws PdfException {
    exportToFile(htmlContent, filePath, null);
    }

  /**

  • 导出PDF文件的字节数组
  • @param htmlContent html格式的文件内容
  • @return
    */
    public static byte[] exportToByteArray(String htmlContent) {
    return exportToByteArray(htmlContent, null);
    }

  /**

  • 导出到指定的文件目录中

  • @param htmlContent html格式的文件内容

  • @param filePath 导出的目标路径

  • @param pageEventHelper

  • @throws PdfException
    */
    public static void exportToFile(String htmlContent, String filePath, PdfPageEventHelper pageEventHelper) throws PdfException {

    FileOutputStream outputStream = null;
    try {
    File file = new File(filePath);
    if (!file.getParentFile().exists()) {
    file.getParentFile().mkdirs();
    }

     // 设置输出路径
     outputStream = new FileOutputStream(filePath);
    
     // 设置文档大小
     Document document = new Document(PageSize.A4);
     PdfWriter writer = PdfWriter.getInstance(document, outputStream);
    
     // 设置页眉页脚
     writer.setPageEvent(pageEventHelper);
    
     // 输出为PDF文件
     convertToPDF(writer, document, htmlContent);
    

    } catch (Exception e) {
    throw new PdfException(e);
    } finally {
    closeStream(outputStream);
    }
    }

  /**

  • 导出PDF文件的字节数组

  • @param htmlContent html格式的文件内容

  • @param pageEventHelper

  • @return
    */
    public static byte[] exportToByteArray(String htmlContent, PdfPageEventHelper pageEventHelper) {
    ByteArrayOutputStream outputStream = null;
    try {
    // 设置输出路径
    outputStream = new ByteArrayOutputStream();

     // 设置文档大小
     Document document = new Document(PageSize.A4);
     PdfWriter writer = PdfWriter.getInstance(document, outputStream);
    
     // 设置页眉页脚
     writer.setPageEvent(pageEventHelper);
    
     // 输出为PDF文件
     convertToPDF(writer, document, htmlContent);
     return outputStream.toByteArray();
    

    } catch (Exception e) {
    throw new RuntimeException(e);
    } finally {
    closeStream(outputStream);
    }
    }

  /**

  • @description PDF文件生成
    */
    private static void convertToPDF(PdfWriter writer, Document document, String htmlString) {
    try {
    // 获取字体路径
    String fontPath = getFontPath();
    document.open();
    XMLWorkerHelper.getInstance().parseXHtml(writer, document, new ByteArrayInputStream(htmlString.getBytes(Charset.forName(“UTF-8”))),
    XMLWorkerHelper.class.getResourceAsStream("/default.css"), Charset.forName(“UTF-8”),
    new PdfFont());
    } catch (IOException e) {
    throw new RuntimeException(“PDF文件生成异常”, e);
    } finally {
    document.close();
    }
    }

  /**

  • @description 获取字体设置路径
    */
    public static String getFontPath() {
    String classpath = PdfUtil.class.getClassLoader().getResource("").getPath();
    return classpath + “ftl/fonts”;
    }

  private static void closeStream(OutputStream outputStream){
  if (outputStream != null) {
  try {
  outputStream.close();
  } catch (IOException e) {
  logger.error(“关闭文件流异常”, e);
  }
  }
  }
  }

//解决linux系统下没有中文丢失问题
public class PdfFont extends XMLWorkerFontProvider{
private static final Logger logger = LoggerFactory.getLogger(PdfFont.class);
public PdfFont(){
super(null,null);
}
@Override
public Font getFont(final String fontname, String encoding, float size, final int style) {

    Font FontChinese = null;
    try {
        BaseFont bfChinese = BaseFont.createFont("STSong-Light",
                "UniGB-UCS2-H", BaseFont.NOT_EMBEDDED);
        FontChinese = new Font(bfChinese, 12, Font.NORMAL);
    } catch (Exception e) {
        logger.error("字体出错",e);
    }
    if(FontChinese==null)
        FontChinese = super.getFont(fontname, encoding, size, style);
    return FontChinese;
}

//controller中 直接将文件下载
response.reset();
response.setCharacterEncoding(“utf-8”);
response.setContentType(“application/pdf”); // pdf格式

        response.setHeader("Content-Disposition", "attachment; filename="+new String( ("XXX" + ".pdf").getBytes(),
                "iso-8859-1"));
        OutputStream os = response.getOutputStream();   //直接下载导出
        os.write(bytes);
        os.flush();
        os.close();

//直接将流放入response中 可实现预览
OutputStream ostream = response.getOutputStream();
ostream.write(bytes);
os.flush();
os.close();