itext5和itext7操作pdf平铺和图层叠加(tiling, and N-upping)

区别

itext5 生成pdf版本:1.4(Acrobat5.x)

itext7 生成pdf版本:1.7(Acrobat8.x)

iText7生成的pdf文件大, itext7 Java库更加系统和完善

iText测试版本和功能描述

itext5

<dependency>

    <groupId>com.itextpdf</groupId>

    <artifactId>itextpdf</artifactId>

    <version>5.5.13</version>

</dependency>

itext7

<dependency>

    <groupId>com.itextpdf</groupId>

    <artifactId>itext7-core</artifactId>

    <version>7.1.8</version>

    <type>pom</type>

</dependency>

描述: pdf稿件平铺和生成条形码

示例代码

itext5

package com.demo.controller;

import com.itextpdf.text.*;

import com.itextpdf.text.Rectangle;

import com.itextpdf.text.pdf.*;

import java.io.FileOutputStream;

import java.io.IOException;

import com.itextpdf.text.Document;

import com.itextpdf.text.pdf.BaseFont;

import com.itextpdf.text.pdf.PdfContentByte;

import com.itextpdf.text.pdf.PdfImportedPage;

import com.itextpdf.text.pdf.PdfReader;

import com.itextpdf.text.pdf.PdfWriter;

import java.io.File;

import java.util.ArrayList;

import java.util.List;

public class HelloController {

    public static final String OUTDIR = "results/big/";

    private float _PT_CM_RATE = 0.352736F;

    private static float _PILLOW_HEIGHT = 70F / 0.352736F;

    private static float _PILLOW_WIDTH = 47F / 0.352736F;

    public static void main(String args[]) throws IOException {

        File file = new File(OUTDIR);

        file.getParentFile().mkdirs();

        try {

            double random = Math.random();

            new HelloController().createCodePdf(OUTDIR+"all"+random+".pdf");

            new HelloController().createRowPdf(OUTDIR+"row"+random+".pdf");

        }catch (Exception e)

        {

            System.out.println(e.getMessage());

        }

    }

    public void createCodePdf(String dest) throws IOException, DocumentException {

        List<String> arrayList = new ArrayList<String>();

        arrayList.add("results/test_three_01.pdf");

        arrayList.add("results/test_three_02.pdf");

        arrayList.add("results/test_three_03.pdf");

        arrayList.add("results/test_three_04.pdf");

        arrayList.add("results/test_three_05.pdf");

        arrayList.add("results/test_three_06.pdf");

        arrayList.add("results/test_three_07.pdf");

        arrayList.add("results/test_three_08.pdf");

        arrayList.add("results/test_three_09.pdf");

        arrayList.add("results/test_three_10.pdf");

        //生成文件的pdfDoc对象

        Document document = new Document(new Rectangle(707 / _PT_CM_RATE, 1081 / _PT_CM_RATE));

        PdfWriter pdfWriter = PdfWriter.getInstance(document, new FileOutputStream(dest));

        document.open();

        PdfContentByte canvas = pdfWriter.getDirectContent();

        //1.添加两边黑光标

        PdfReader pdfBlack = new PdfReader("results/black_47.pdf");

        Rectangle pageSize = pdfBlack.getPageSize(1);

        final float pdfBlackWidth = pageSize.getWidth();

        PdfImportedPage pageBlackCopy = pdfWriter.getImportedPage(pdfBlack, 1);

        int rowWorkNum = 18;

        int rowCodeNum = 5;

        //2.遍历稿件list

        for (int i = 1; i <= rowWorkNum+rowCodeNum; i++)

        {

            canvas.addTemplate(pageBlackCopy, 0, _PILLOW_WIDTH*(i-1) );

            canvas.addTemplate(pageBlackCopy,_PILLOW_HEIGHT*10+pdfBlackWidth,_PILLOW_WIDTH*(i-1));

        }

        int j = 0;

        PdfImportedPage workPdfPage;

        for (String work : arrayList) {

            //读取稿件内容

            PdfReader workPdf = new PdfReader(work);

            workPdfPage = pdfWriter.getImportedPage(workPdf, 1);

            for (int i = 1; i <= rowWorkNum; i++) {

                canvas.addTemplate(workPdfPage, 0, -1, 1, 0, _PILLOW_HEIGHT * j + pdfBlackWidth, _PILLOW_WIDTH * (i + 5));

            }

            j++;

        }

        //3.遍历条形码

        //遍历条形码底图

        PdfReader pdfBlackCode = new PdfReader("results/black_100.pdf");

        PdfImportedPage pageBlackCodeCopy = pdfWriter.getImportedPage(pdfBlackCode, 1);

        for(int jj=1; jj<=10; jj++){

            Barcode128 barcode = new Barcode128();

            barcode.setCodeType(Barcode.CODE128);

            barcode.setBarHeight(14);

            barcode.setX(0.4F);

            barcode.setBaseline(23f);

            barcode.setCode("1954745454544_3-"+jj);

            barcode.setTextAlignment(0);

            PdfTemplate templateWithBarcode = barcode.createTemplateWithBarcode(canvas, BaseColor.BLACK, BaseColor.BLACK);

            barcode.setFont(BaseFont.createFont("c:/windows/fonts/simkai.ttf", BaseFont.IDENTITY_H,false));

            barcode.setAltText("进口量煎熬副科级第三方");

            PdfTemplate templateWithBarcodeText = barcode.createTemplateWithBarcode(canvas, BaseColor.BLACK, BaseColor.BLACK);

            barcode.setAltText("");

            PdfTemplate templateWithBarcodeNone = barcode.createTemplateWithBarcode(canvas, BaseColor.BLACK, BaseColor.BLACK);

            for(int i=1; i<=rowCodeNum; i++){

                canvas.addTemplate(pageBlackCodeCopy,0,-1,1,0,(jj-1)*_PILLOW_HEIGHT+pdfBlackWidth,(i)*_PILLOW_WIDTH);

                canvas.addTemplate(templateWithBarcodeText, 0, -1, 1, 0, 52 + (jj - 1) * _PILLOW_HEIGHT + pdfBlackWidth, (i) * _PILLOW_WIDTH - 25);

                canvas.addTemplate(templateWithBarcode, 0, -1, 1, 0, 67 + (jj - 1) * _PILLOW_HEIGHT + pdfBlackWidth, (i) * _PILLOW_WIDTH - 25);

                canvas.addTemplate(templateWithBarcodeNone, 0, -1, 1, 0, 82 + (jj - 1) * _PILLOW_HEIGHT + pdfBlackWidth, (i) * _PILLOW_WIDTH - 25);

                canvas.addTemplate(templateWithBarcodeNone, 0, -1, 1, 0, 97 + (jj - 1) * _PILLOW_HEIGHT + pdfBlackWidth, (i) * _PILLOW_WIDTH - 25);

            }

        }

        //4.关闭资源

        document.close();

        pdfBlack.close();

        pdfBlackCode.close();

    }

    public void createRowPdf(String dest) throws IOException , DocumentException{

        List<String> arrayList = new ArrayList<String>();

        arrayList.add("results/test_three_01.pdf");

        arrayList.add("results/test_three_02.pdf");

        arrayList.add("results/test_three_03.pdf");

        arrayList.add("results/test_three_04.pdf");

        arrayList.add("results/test_three_05.pdf");

        arrayList.add("results/test_three_06.pdf");

        arrayList.add("results/test_three_07.pdf");

        arrayList.add("results/test_three_08.pdf");

        arrayList.add("results/test_three_09.pdf");

        arrayList.add("results/test_three_10.pdf");

        //生成文件的pdfDoc对象

        Document document = new Document(new Rectangle(707 / _PT_CM_RATE, 47/ _PT_CM_RATE));

        PdfWriter pdfWriter = PdfWriter.getInstance(document, new FileOutputStream(dest));

        document.open();

        PdfContentByte canvas = pdfWriter.getDirectContent();

        //1.添加两边黑光标

        PdfReader pdfBlack = new PdfReader("results/black_47.pdf");

        Rectangle pageSize = pdfBlack.getPageSize(1);

        final float pdfBlackWidth = pageSize.getWidth();

        PdfImportedPage pageBlackCopy = pdfWriter.getImportedPage(pdfBlack, 1);

        int rowWorkNum = 1;

        int rowCodeNum = 0;

        //2.遍历稿件list

        for (int i = 1; i <= rowWorkNum+rowCodeNum; i++)

        {

            canvas.addTemplate(pageBlackCopy, 0, _PILLOW_WIDTH*(i-1) );

            canvas.addTemplate(pageBlackCopy,_PILLOW_HEIGHT*10+pdfBlackWidth,_PILLOW_WIDTH*(i-1));

        }

        int j = 0;

        PdfImportedPage workPdfPage;

        for (String work : arrayList) {

            //读取稿件内容

            PdfReader workPdf = new PdfReader(work);

            workPdfPage = pdfWriter.getImportedPage(workPdf, 1);

            for (int i = 1; i <= rowWorkNum; i++) {

                canvas.addTemplate(workPdfPage, 0, -1, 1, 0, _PILLOW_HEIGHT * j + pdfBlackWidth, _PILLOW_WIDTH * (i));

            }

            j++;

        }

        //关闭资源

        document.close();

        pdfBlack.close();

    }

}

itext7

package com.demo.controller;

import com.itextpdf.io.font.PdfEncodings;

import com.itextpdf.io.font.constants.StandardFonts;

import com.itextpdf.io.image.ImageDataFactory;

import com.itextpdf.kernel.font.PdfFont;

import com.itextpdf.kernel.font.PdfFontFactory;

import com.itextpdf.barcodes.Barcode128;

import com.itextpdf.barcodes.Barcode1D;

import com.itextpdf.io.font.FontConstants;

import com.itextpdf.io.image.ImageData;

import com.itextpdf.io.image.ImageType;

import com.itextpdf.kernel.geom.PageSize;

import com.itextpdf.kernel.geom.Rectangle;

import com.itextpdf.kernel.pdf.PdfDocument;

import com.itextpdf.kernel.pdf.PdfPage;

import com.itextpdf.kernel.pdf.PdfReader;

import com.itextpdf.kernel.pdf.PdfWriter;

import com.itextpdf.kernel.pdf.canvas.PdfCanvas;

import com.itextpdf.kernel.pdf.xobject.PdfFormXObject;

import com.itextpdf.kernel.geom.AffineTransform;

import com.itextpdf.layout.Document;

import com.itextpdf.layout.element.Paragraph;

import com.itextpdf.kernel.PdfException;

import com.itextpdf.kernel.colors.Color;

import com.itextpdf.kernel.colors.ColorConstants;

import com.itextpdf.kernel.colors.DeviceRgb;

import org.apache.pdfbox.cos.COSBase;

import org.apache.pdfbox.cos.COSDictionary;

import org.apache.pdfbox.cos.COSName;

import org.apache.pdfbox.pdmodel.PDDocument;

import org.apache.pdfbox.pdmodel.PDPage;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.ResponseBody;

import java.awt.*;

import java.awt.image.BufferedImage;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import com.itextpdf.layout.element.Text;

import static com.itextpdf.svg.SvgConstants.Tags.IMAGE;

public class HelloController {

    public static final String DEST = "results/big/wwww"+Math.random()+".pdf";

    private float _PT_CM_RATE = 0.352736F;

    private static float _PILLOW_HEIGHT = 70F / 0.352736F;

    private static float _PILLOW_WIDTH = 47F / 0.352736F;

    public static void main(String args[]) throws IOException {

        File file = new File(DEST);

        file.getParentFile().mkdirs();

//        new HelloController().createCodePdf(DEST);

        new HelloController().createRowPdf(DEST);

    }

    public void createCodePdf(String dest) throws IOException {

        List<String> arrayList = new ArrayList<String>();

        arrayList.add("results/test_three_01.pdf");

        arrayList.add("results/test_three_02.pdf");

        arrayList.add("results/test_three_03.pdf");

        arrayList.add("results/test_three_04.pdf");

        arrayList.add("results/test_three_05.pdf");

        arrayList.add("results/test_three_06.pdf");

        arrayList.add("results/test_three_07.pdf");

        arrayList.add("results/test_three_08.pdf");

        arrayList.add("results/test_three_09.pdf");

        arrayList.add("results/test_three_10.pdf");

        //生成文件的pdfDoc对象

        PdfWriter dfWriter = new PdfWriter(dest);

        dfWriter.setSmartMode(true);

        PdfDocument pdf = new PdfDocument(dfWriter);

        PageSize nUpPageSize = new PageSize(707 / _PT_CM_RATE, 1081 / _PT_CM_RATE);

//        PageSize nUpPageSize = new PageSize(707 / _PT_CM_RATE, 510 / _PT_CM_RATE);

        PdfPage page = pdf.addNewPage(nUpPageSize);

        //画布的生成

        PdfCanvas canvas = new PdfCanvas(page);

        //Scale page

        AffineTransform transformationMatrix = AffineTransform.getScaleInstance(1, 1);

        canvas.concatMatrix(transformationMatrix);//不旋转

        //添加右侧黑光标

        PdfDocument pdfBlack = new PdfDocument(new PdfReader("results/black_47.pdf"));

        PdfPage blackPage = pdfBlack.getPage(1);

        Rectangle origBlack = blackPage.getPageSize();

        PdfFormXObject pageBlackCopy = blackPage.copyAsFormXObject(pdf);

        int rowWorkNum = 18;

        int rowCodeNum = 5;

        //遍历稿件list

        for (int i = 1; i <= rowWorkNum; i++)

            canvas.addXObject(pageBlackCopy, 0, _PILLOW_WIDTH*(i+4) );

        int j = 0;

        for (String work : arrayList) {

            //System.out.println(work);

            //读取稿件内容

            PdfDocument workPdf = new PdfDocument(new PdfReader(work));

            PdfPage workPdfPage = workPdf.getPage(1);

            PdfFormXObject workPdfPageForm = workPdfPage.copyAsFormXObject(pdf);

            for (int i = 1; i <= rowWorkNum; i++) {

                canvas.addXObject(workPdfPageForm, 0, -1, 1, 0, _PILLOW_HEIGHT * j + origBlack.getWidth(), _PILLOW_WIDTH * (i + 5));

            }

            workPdf.close();

            j++;

        }

        for (int i = 1; i <= rowWorkNum; i++)

            canvas.addXObject(pageBlackCopy,_PILLOW_HEIGHT*10+origBlack.getWidth(),_PILLOW_WIDTH*(i+4));

        //遍历条形码

        //遍历条形码底图

        PdfDocument codeBackPdf = new PdfDocument(new PdfReader("results/black_100.pdf"));

        PdfPage codeBackPage = codeBackPdf.getPage(1);

        Rectangle codeBackPageRectangle = codeBackPage.getPageSize();

        PdfFormXObject codeBackPageForm = codeBackPage.copyAsFormXObject(pdf);

        for(int i=1; i<=rowCodeNum; i++){

            canvas.addXObject(pageBlackCopy, 0, _PILLOW_WIDTH*(i-1) );

            for(int jj=1; jj<=10; jj++){

                canvas.addXObject(codeBackPageForm,0,-1,1,0,(jj-1)*_PILLOW_HEIGHT+origBlack.getWidth(),(i)*_PILLOW_WIDTH);

                String myString = "1954745454544_3-1";

                Barcode128 barcode = new Barcode128(pdf);

                barcode.setCode(myString);

                barcode.setCodeType(Barcode128.CODE128);

                barcode.setBaseline(23f);

                barcode.setAltText("进口量煎熬副科级第三方");

                barcode.setFont(PdfFontFactory.createFont("c:/windows/fonts/simkai.ttf", PdfEncodings.IDENTITY_H,false));

                barcode.setTextAlignment(Barcode1D.ALIGN_LEFT);

                barcode.setBarHeight(14);

                barcode.setX(0.45F);

                PdfFormXObject pdfImg = barcode.createFormXObject(pdf);

                barcode.setAltText("1954745454544_3-1");

                PdfFormXObject pdfImgCode = barcode.createFormXObject(pdf);

                barcode.setAltText("");

                PdfFormXObject pdfImgOnly = barcode.createFormXObject(pdf);

                //canvas.add(p);

                canvas.addXObject(pdfImg,0,-1,1,0,52+(jj-1)*_PILLOW_HEIGHT+origBlack.getWidth(),(i)*_PILLOW_WIDTH-25);

                canvas.addXObject(pdfImgCode,0,-1,1,0,67+(jj-1)*_PILLOW_HEIGHT+origBlack.getWidth(),(i)*_PILLOW_WIDTH-25);

                canvas.addXObject(pdfImgOnly,0,-1,1,0,82+(jj-1)*_PILLOW_HEIGHT+origBlack.getWidth(),(i)*_PILLOW_WIDTH-25);

                canvas.addXObject(pdfImgOnly,0,-1,1,0,97+(jj-1)*_PILLOW_HEIGHT+origBlack.getWidth(),(i)*_PILLOW_WIDTH-25);

            }

            canvas.addXObject(pageBlackCopy,_PILLOW_HEIGHT*10+origBlack.getWidth(),_PILLOW_WIDTH*(i-1));

        }

        pdfBlack.close();

        pdf.close();

    }

    public void createRowPdf(String dest) throws IOException {

        List<String> arrayList = new ArrayList<String>();

        arrayList.add("results/test_three_01.pdf");

        arrayList.add("results/test_three_02.pdf");

        arrayList.add("results/test_three_03.pdf");

        arrayList.add("results/test_three_04.pdf");

        arrayList.add("results/test_three_05.pdf");

        arrayList.add("results/test_three_06.pdf");

        arrayList.add("results/test_three_07.pdf");

        arrayList.add("results/test_three_08.pdf");

        arrayList.add("results/test_three_09.pdf");

        arrayList.add("results/test_three_10.pdf");

        //生成文件的pdfDoc对象

        PdfDocument pdf = new PdfDocument(new PdfWriter(dest));

        System.out.println(pdf.getPdfVersion());

        PageSize nUpPageSize = new PageSize(707 / _PT_CM_RATE, 47 / _PT_CM_RATE);

        PdfPage page = pdf.addNewPage(nUpPageSize);

        //画布的生成

        PdfCanvas canvas = new PdfCanvas(page);

        //Scale page

        AffineTransform transformationMatrix = AffineTransform.getScaleInstance(1, 1);

        canvas.concatMatrix(transformationMatrix);//不旋转

        //添加右侧黑光标

        PdfDocument pdfBlack = new PdfDocument(new PdfReader("results/black_47.pdf"));

        PdfPage blackPage = pdfBlack.getPage(1);

        Rectangle origBlack = blackPage.getPageSize();

        PdfFormXObject pageBlackCopy = blackPage.copyAsFormXObject(pdf);

        canvas.addXObject(pageBlackCopy, 0, 0);

        //遍历稿件list

        int j = 0;

        for (String work : arrayList) {

            //读取稿件内容

            PdfDocument workPdf = new PdfDocument(new PdfReader(work));

            PdfPage workPdfPage = workPdf.getPage(1);

            //pdf转化为图片资源

//            byte[] contentBytes = workPdfPage.getContentBytes();

//            ImageData image = ImageDataFactory.create(contentBytes);

//            canvas.addImage(image, 0,-1,1,0,_PILLOW_HEIGHT*j+origBlack.getWidth(),_PILLOW_WIDTH);

            //pdf转化为formX

            PdfFormXObject workPdfPageForm = workPdfPage.copyAsFormXObject(pdf);

            canvas.addXObject(workPdfPageForm, 0,-1,1,0,_PILLOW_HEIGHT*j+origBlack.getWidth(),_PILLOW_WIDTH);

            workPdf.close();

            j++;

        }

        canvas.addXObject(pageBlackCopy,_PILLOW_HEIGHT*10+origBlack.getWidth(),0);

        pdfBlack.close();

        pdf.close();

    }

}

参考文章

https://itextpdf.com/en/resources/books/itext-7-jump-start-tutorial-java/chapter-6-reusing-existing-pdf-documents

https://itextpdf.com/en/resources/examples/itext-5-legacy/chapter-6-working-existing-pdfs

itext5和itext7操作pdf平铺和图层叠加(tiling, and N-upping)的更多相关文章

Java 设置PDF平铺图片背景（水印）
一.概述及环境准备本文介绍使用免费版PDF库-Free Spire.PDF for Java加载图片来设置成PDF平铺图片背景的效果,也可以作为平铺图片水印来使用:编辑代码前,需要先导入jar文件, ...
UIImage图片处理，旋转、截取、平铺、缩放等操作
来源:iOS_小松哥链接:http://www.jianshu.com/p/9ab1205f5166 有时候我们需要处理图片,比如改变大小,旋转,截取等等,所以今天说一说图片处理相关的一些操作. 本 ...
5 分钟掌握 JS 实用窍门技巧，帮你快速撸码--- 删除数组尾部元素、E6对象解构、async/await、操作平铺嵌套多维数组等
1. 删除数组尾部元素一个简单方法就是改变数组的length值: const arr = [11, 22, 33, 44, 55, 66]; arr.length = 3; console.log( ...
JSON平铺功能的实现(JS操作JSON数据)
一.什么是JSON平铺 JSON平铺分成两种: 平铺的json转树结构的json 例如: { a: 'value', b: 'b1.value' } // 转换成=> { a: 'value', ...
深度学习原理与框架-递归神经网络-RNN_exmaple(代码) 1.rnn.BasicLSTMCell(构造基本网络) 2.tf.nn.dynamic_rnn(执行rnn网络) 3.tf.expand_dim(增加输入数据的维度) 4.tf.tile(在某个维度上按照倍数进行平铺迭代) 5.tf.squeeze(去除维度上为1的维度)
1. rnn.BasicLSTMCell(num_hidden) # 构造单层的lstm网络结构参数说明:num_hidden表示隐藏层的个数 2.tf.nn.dynamic_rnn(cell, ...
建模：通过ES平铺关系型数据库多表的数据
问:建模要从一个限界上下文中来建模,是否可以简单的把几张表进行笛卡尔乘积方式的平铺? 答:不能,原因之一,数据量会急剧增长:原因之二,这样的平铺是毫无意义的,必须要定义一个维度,在这个维度上根据需求约 ...
C# 处理PPT水印（三）—— 在PPT中添加多行（平铺）文本水印效果
在PPT幻灯片中,可通过添加形状的方式,来实现类似水印的效果,可添加单一文本水印效果,即幻灯片中只有一个文本水印:也可以添加多行(平铺)文本水印效果,即幻灯片中以一定方式平铺排列多个文本水印效果.本文 ...
Java使用iText7生成PDF
前言我们之前使用js库html2canvas + jspdf实现html转PDF.图片,并下载(详情请戳:html页面转PDF.图片操作记录),大致原理是将页面塞到画布里,以图片的方式放到PDF中, ...
Mac下的平铺式桌面 - Yabai
Mac下的平铺式桌面 - Yabai 近来无事,凑着周末休息的时间,想折腾一下 Mac.很久之前就有朋友给我推荐过一款名为"Yabai"的平铺式桌面管理软件,今天,就折腾起来了. ...

随机推荐

iptables总结,开启端口,查看端口占用情况
Centos查看端口占用情况和开启端口命令 Centos查看端口占用情况命令,比如查看80端口占用情况使用如下命令: lsof -i tcp:80 列出所有端口 netstat -ntlp mac上查 ...
API自动化测试指南
我相信自动化技能已经成为高级测试工程师总体技能的标配.敏捷和持续测试破坏了传统的测试自动化实践,导致测试工程师重新考虑自动化的完成方式.当今的自动化工程师需要在GUI的下方深入到API级别完成软件质量 ...
【k8s】kubeadm快速部署Kubernetes
1.Kubernetes 架构图 kubeadm是官方社区推出的一个用于快速部署kubernetes集群的工具. 这个工具能通过两条指令完成一个kubernetes集群的部署: # 创建一个 Mast ...
Batch Normalization批量归一化
BN的深度理解:https://www.cnblogs.com/guoyaohua/p/8724433.html BN: BN的意义:在激活函数之前将输入归一化到高斯分布,控制到激活函数的敏感区域,避 ...
定位布局中关于z-index的一些问题
定位布局中关于z-index的一些问题使不同父元素的子元素不会被其他父元素遮盖背景两父元素相互遮盖(或部分遮盖) html如下 <div class="main"> ...
Hive性能优化（全面）
1.介绍首先,我们来看看Hadoop的计算框架特性,在此特性下会衍生哪些问题? 数据量大不是问题,数据倾斜是个问题. jobs数比较多的作业运行效率相对比较低,比如即使有几百行的表,如果多次关联多次 ...
poj-1511
从1节点到所有节点的最短路和,加上所有节点返回1节点的最短路和,刚开始的方法时间复杂度有毒啊其实只要把边全反向重装一次就好了哈哈哈好了就是这样,套路了一个dijkstra+优先队列 #includ ...
javascript DOM 编程艺术札记2 平稳退化
定义指的是即便浏览器不支持javascript,页面的基础展示功能也不会受到影响的做法. 不能平稳退化的实例 javascript:这种伪协议,它可以通过链接调用javascript函数.比如< ...
Cocos Creator | 飞刀大乱斗开发教程系列（二）
预览效果具体内容 ■ 这一期,主要讲解主页中间人物效果的实现.也就是,在下方列表选择不同人物,上方显示不同的人物,播放不同的效果,即下图的效果实现,此部分也是采用预制 Prefab 进行实现. 英雄 ...
Python 多态与抽象类
一.多态 1.1 什么是多态多态也称"多态性",指的是同一种类型的事物,不同的形态. 在python中的多态指的是让多种类若具备类似的数据属性与方法属性,都统一好命名规范,这样可 ...

itext5和itext7操作pdf平铺和图层叠加(tiling, and N-upping)

区别

iText测试版本和功能描述

示例代码

参考文章

itext5和itext7操作pdf平铺和图层叠加(tiling, and N-upping)的更多相关文章

随机推荐

热门专题