前言

  在制作印章的时候 通过后端计算印章位置坐标，需要 提供pdf页面关键字 即可找到此关键字在pdf中的页数以及x,y 坐标

一、两个基础配置类

1.KeyWordPositionListener   pdf签名帮助类

代码如下（示例）：

讯享网

package com.z.boot.core.util.pdf; import com.itextpdf.awt.geom.Rectangle2D; import com.itextpdf.text.Rectangle; import com.itextpdf.text.pdf.parser.ImageRenderInfo; import com.itextpdf.text.pdf.parser.RenderListener; import com.itextpdf.text.pdf.parser.TextRenderInfo; import java.util.ArrayList; import java.util.List; / * @ClassName KeyWordPositionListener * @Description pdf签名帮助类 * @Date: 2021/3/17 16:57 * @Version 1.0 / public class KeyWordPositionListener implements RenderListener{ private List matches = new ArrayList(); private List allItems = new ArrayList(); private Rectangle curPageSize; / * 匹配的关键字 */ private String keyword; / * 匹配的当前页 */ private Integer pageNumber; public void beginTextBlock() { //do nothing } public void renderText(TextRenderInfo renderInfo) { String content = renderInfo.getText(); content = content.replace("<", "").replace("《", "").replace("(", "").replace("（", "").replace("\"", "").replace("'", "") .replace(">", "").replace("》", "").replace(")", "").replace("）", "").replace("、", "").replace(".", "") .replace("：", "").replace(":", "").replace(" ", ""); Rectangle2D.Float boundingRectange = renderInfo.getBaseline().getBoundingRectange(); MatchItem item = new MatchItem(); item.setContent(content); item.setPageNum(pageNumber); item.setPageWidth(curPageSize.getWidth()); //页面宽度 item.setPageHeight(curPageSize.getHeight()); //页面高度 item.setX(boundingRectange.x); item.setY(boundingRectange.y); item.setRectangeWidth(boundingRectange.getWidth()); //当前块级元素占的宽度 item.setRectangeHeight(boundingRectange.getHeight()); //当前块级元素占的高度 if(content!=null && content!=""){ if(content.equalsIgnoreCase(keyword)) { matches.add(item); } } allItems.add(item);//先保存所有的项 } public void endTextBlock() { //do nothing } public void renderImage(ImageRenderInfo renderInfo) { //do nothing } / * 设置需要匹配的当前页 * @param pageNumber */ public void setPageNumber(Integer pageNumber) { this.pageNumber = pageNumber; } / * 设置需要匹配的关键字，忽略大小写 * @param keyword */ public void setKeyword(String keyword) { this.keyword = keyword; } / * 返回匹配的结果列表 * @return */ public List getMatches() { return matches; } void setCurPageSize(Rectangle rect) { this.curPageSize = rect; } public List getAllItems() { return allItems; } public void setAllItems(List allItems) { this.allItems = allItems; } } 

2.MatchItem 

代码如下（示例）：

讯享网package com.z.boot.core.util.pdf; / * @ClassName MatchItem * @Description * @Date: 2021/3/17 16:57 * @Version 1.0 / public class MatchItem { private Integer pageNum; private Float x; private Float y; private Float pageWidth; private Float pageHeight; private String content; private double rectangeWidth; //块级元素宽度 private double rectangeHeight; //块级元素高度 public Integer getPageNum() { return pageNum; } public void setPageNum(Integer pageNum) { this.pageNum = pageNum; } public Float getX() { return x; } public void setX(Float x) { this.x = x; } public Float getY() { return y; } public void setY(Float y) { this.y = y; } public Float getPageWidth() { return pageWidth; } public void setPageWidth(Float pageWidth) { this.pageWidth = pageWidth; } public Float getPageHeight() { return pageHeight; } public void setPageHeight(Float pageHeight) { this.pageHeight = pageHeight; } public String getContent() { return content; } public void setContent(String content) { this.content = content; } public double getRectangeWidth() { return rectangeWidth; } public void setRectangeWidth(double rectangeWidth) { this.rectangeWidth = rectangeWidth; } public double getRectangeHeight() { return rectangeHeight; } public void setRectangeHeight(double rectangeHeight) { this.rectangeHeight = rectangeHeight; } @Override public String toString() { return "MatchItem [pageNum=" + pageNum + ", x=" + x + ", y=" + y + ", pageWidth=" + pageWidth + ", pageHeight=" + pageHeight + ", content=" + content + "]"; } } 

二、核心计算类

package com.z.boot.core.util.pdf; import com.itextpdf.text.Rectangle; import com.itextpdf.text.pdf.PdfReader; import com.itextpdf.text.pdf.parser.PdfReaderContentParser; import lombok.extern.slf4j.Slf4j; import java.io.IOException; import java.util.List; / * @ClassName QuotationPdf * @Description * @Date: 2021/3/16 10:44 * @Version 1.0 / @Slf4j public class QuotationPdf { / * @param filepath * @param keyWords * @return float[] * @Date 2021/3/17 16:57 * @Description 用于供外部类调用获取关键字所在PDF文件坐标 * @Version 1.0 */ public static MatchItem getKeyWordsByPath(String filepath, String keyWords) throws Exception { try { PdfReader pdfReader = new PdfReader(filepath); int pageCount= pdfReader.getNumberOfPages(); return matchPage(pdfReader,pageCount, keyWords); } catch (IOException e) { e.printStackTrace(); return null; } } / * 在文件中寻找指定的文字内容 * * @param reader * @param pageNumber * @param keyword * @return * @throws Exception */ public static MatchItem matchPage(PdfReader reader, Integer pageNumber, String keyword) throws Exception { MatchItem matchItem = null; PdfReaderContentParser parse = new PdfReaderContentParser(reader); KeyWordPositionListener renderListener = new KeyWordPositionListener(); renderListener.setKeyword(keyword); int page = 0; for (page = 1; page <= pageNumber; page++) { renderListener.setPageNumber(page); Rectangle rectangle = reader.getPageSize(page); renderListener.setCurPageSize(rectangle); parse.processContent(page, renderListener); matchItem = findKeywordItems(renderListener, keyword); if(null != matchItem) { matchItem.setPageNum(page); break; } } reader.close(); return matchItem; } / * 找到匹配的关键词块 * * @param renderListener * @param keyword * @return */ public static MatchItem findKeywordItems(KeyWordPositionListener renderListener, String keyword) { // 先判断本页中是否存在关键词 List allItems = renderListener.getAllItems();// 所有块LIST StringBuilder sbtemp = new StringBuilder(""); for (int i = 0; i < allItems.size(); i++) {// 将一页中所有的块内容连接起来组成一个字符串。(空格用“正”代替) sbtemp.append(((MatchItem) allItems.get(i)).getContent()); } int index = sbtemp.toString().indexOf(keyword); System.out.println(sbtemp.toString()); if (index == -1) {// 一页组成的字符串没有关键词，直接return return null; } //获取关键词与块内容完全匹配的项 List matches = renderListener.getMatches(); if(null == matches || matches.size()<=0){ //不存在，取本页中连续 拼接块内容 第一个关键字的位置 //当拼接的长度超过或等于关键字在此页内容中出现的位置，即为找到 sbtemp = new StringBuilder(""); for (int i = 0; i < allItems.size(); i++) { sbtemp.append(((MatchItem) allItems.get(i)).getContent()); if(sbtemp.toString().length() >= index+1){ matches.add(allItems.get(i)); break; } } } //第二种方式，跟上面是一样的，可以自行研究 // if(null == matches || matches.size()<=0){ // //若还为空，第二种情况：多个块内容拼成一个关键词 取连续的几个块内容拼接起来 // //1.若关键字包含context继续拼接；2.若关键字等于context即找到 // sbtemp = new StringBuffer(""); // int ItmeIndex = 0; //块级元素计数器 // for (int i = 0; i < allItems.size(); i++) { // String itemText = ((MatchItem) allItems.get(i)).getContent(); // sbtemp.append(itemText); // if(keyword.contains(sbtemp.toString()) ){ // // }else if(keyword.equals(sbtemp.toString())){ // matches.add(allItems.get(i)); // break; // }else if(sbtemp.toString().contains(keyword)){ // //被块元素包含 // int index1 = itemText.indexOf(keyword); // double rectangeWidth = ((MatchItem) allItems.get(i)).getRectangeWidth(); //块级元素的宽度 // double oneWidth = rectangeWidth/itemText.length(); //单个字体的宽度 // double finalWidth = (index1+Math.rint(keyword.length()/2) ) * oneWidth + ((MatchItem) allItems.get(i)).getX(); // ((MatchItem) allItems.get(i)).setX((float) finalWidth); // matches.add(allItems.get(i)); // break; // }else{ // sbtemp = new StringBuffer(""); // } // } // } if(null != matches && matches.size()>0){ return (MatchItem) matches.get(0); }else{ return null; } } / * @param filepath * @return float[] * @Date 18:24 2020/3/7 * @Description 用于供外部类获取PDF高度和宽度 */ public static float[] getWidthAndHeightByPath(String filepath, int page) { float[] coordinate = null; try { PdfReader pdfReader = new PdfReader(filepath); Rectangle pageSize = pdfReader.getPageSize(page); float height = pageSize.getHeight(); float width = pageSize.getWidth(); System.out.println("width = " + width + ", height = " + height); float[] coordinate1 = {width, height}; pdfReader.close(); return coordinate1; // Document document = new Document(pdfReader.getPageSize(1)); Document document = new Document(PageSize.A4.rotate(), 0, 0, 30, 0); // // 获取页面宽度 // float widths = document.getPageSize().getWidth(); // // 获取页面高度 // float heights = document.getPageSize().getHeight(); // System.out.println("widths = "+widths+", heights = "+heights); } catch (IOException e) { e.printStackTrace(); return coordinate; } } public static void main(String[] args) throws Exception { String filePath = "E:\\work\\bin\\wenlinworkspace\\repository\\laboratoryFile\\message\\wordtemp\\2020-12-14\\8aee5d47faa4acee6d066efcf7.pdf"; MatchItem a = getKeyWordsByPath(filePath, "bm_g_12443_1#_ResultData_32"); System.out.println("width = " + a.getX() + ", height = " + a.getY() + ",page = " + a.getPageNum()); // // float[] b = getWidthAndHeightByPath(filePath, Integer.parseInt(a.get("page").toString())); System.out.println(a.getPageWidth()+"-----"+a.getPageHeight()); float x = (a.getX() - 35F) / a.getPageWidth(); float y = (a.getY() - 52.5F) / a.getPageHeight(); System.out.println("x = " + x + ", y = " + y); } } 

三、使用 

讯享网public static void main(String[] args) throws Exception { String filePath = "E:\\work\\bin\\wenlinworkspace\\repository\\laboratoryFile\\message\\wordtemp\\2020-12-14\\8aee5d47faa4acee6d066efcf7.pdf"; MatchItem a = getKeyWordsByPath(filePath, "bm_g_12443_1#_ResultData_32"); System.out.println("width = " + a.getX() + ", height = " + a.getY() + ",page = " + a.getPageNum()); // // float[] b = getWidthAndHeightByPath(filePath, Integer.parseInt(a.get("page").toString())); System.out.println(a.getPageWidth()+"-----"+a.getPageHeight()); float x = (a.getX() - 35F) / a.getPageWidth(); float y = (a.getY() - 52.5F) / a.getPageHeight(); System.out.println("x = " + x + ", y = " + y); }

MatchItem position = QuotationPdf.getKeyWordsByPath(pdfPath,"合同章_01"); //position 里面包含了 所能用到的所有参数 横纵长度，以及页面长宽 //页面比例 需自行计算