Java中字符串根據(jù)寬度(像素)換行的問(wèn)題
更新時(shí)間：2021年09月01日 14:25:19 作者：HealerJean.
這篇文章主要介紹了Java中字符串根據(jù)寬度(像素)換行的問(wèn)題，具有很好的參考價(jià)值，希望對(duì)大家有所幫助。如有錯(cuò)誤或未考慮完全的地方，望不吝賜教
Java 字符串根據(jù)寬度(像素)換行
在一些場(chǎng)景下，我們經(jīng)常會(huì)通過(guò)判斷字符串的長(zhǎng)度，比如個(gè)數(shù)來(lái)實(shí)現(xiàn)換行，但是中文、英文、數(shù)字、其實(shí)在展示的時(shí)候同樣長(zhǎng)度的字符串，其實(shí)它的寬度是不一樣的，這也是們我通俗意義上說(shuō)的寬度(像素)
根據(jù)像素寬度進(jìn)行換行
需求：
/**
* 10、自己做圖片 ，根據(jù)文本寬度進(jìn)行換行
*/
@Test
public void creatMyImage(){
//整體圖合成
BufferedImage bufferedImage = new BufferedImage(500, 500, BufferedImage.TYPE_INT_RGB);
//設(shè)置圖片的背景色
Graphics2D main = bufferedImage.createGraphics();
main.fillRect(0, 0, 500, 500);
String text = "111122223所以比傳統(tǒng)紙巾更環(huán)保3334441比傳統(tǒng)紙巾更環(huán)11111111111111122223所以比傳統(tǒng)紙巾更環(huán)保3334441比傳統(tǒng)紙巾更環(huán)11111111111111122223所以比傳統(tǒng)紙巾更環(huán)保3334441比傳統(tǒng)紙巾更環(huán)11111111111111122223所以比傳統(tǒng)紙巾更環(huán)保3334441比傳統(tǒng)紙巾更環(huán)11111111111";
Graphics2D textG = bufferedImage.createGraphics() ;
textG.setColor(new Color(37,37,37));
Font hualaoContentFont = new Font("PingFang SC", Font.PLAIN, 20);
textG.setFont(hualaoContentFont);
textG.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_GASP);
drawString(textG,text,30,100,4,10,50,true,false);
//存儲(chǔ)到本地
String saveFilePath = "/Users/healerjean/Desktop/new.png";
saveImageToLocalDir(bufferedImage, saveFilePath);
}
/**
*
* @param g
* @param text 文本
* @param lineHeight 行高（注意字體大小的控制哦）
* @param maxWidth 行寬
* @param maxLine 最大行數(shù)
* @param left 左邊距 //整段文字的左邊距
* @param top 上邊距 //整頓文字的上邊距
* @param trim 是否修剪文本（1、去除首尾空格，2、將多個(gè)換行符替換為一個(gè)）
* @param lineIndent 是否首行縮進(jìn)
*/
public static void drawString(Graphics2D g, String text, float lineHeight, float maxWidth, int maxLine, float left,
float top, boolean trim, boolean lineIndent) {
if (text == null || text.length() == 0) return;
if(trim) {
text = text.replaceAll("\\n+", "\n").trim();
}
if(lineIndent) {
text = " " + text.replaceAll("\\n", "\n ");
}
drawString(g, text, lineHeight, maxWidth, maxLine, left, top);
}
/**
*
* @param g
* @param text 文本
* @param lineHeight 行高
* @param maxWidth 行寬
* @param maxLine 最大行數(shù)
* @param left 左邊距
* @param top 上邊距
*/
private static void drawString(Graphics2D g, String text, float lineHeight, float maxWidth, int maxLine, float left,
float top) {
if (text == null || text.length() == 0) return;
FontMetrics fm = g.getFontMetrics();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < text.length(); i++) {
char c = text.charAt(i);
sb.append(c);
int stringWidth = fm.stringWidth(sb.toString());
if (c == '\n' || stringWidth > maxWidth) {
if(c == '\n') {
i += 1;
}
if (maxLine > 1) {
g.drawString(text.substring(0, i), left, top);
drawString(g, text.substring(i), lineHeight, maxWidth, maxLine - 1, left, top + lineHeight);
} else {
g.drawString(text.substring(0, i - 1) + "…", left, top);
}
return;
}
}
g.drawString(text, left, top);
}
Java字符串根據(jù)寬度(像素)進(jìn)行換行及Pdf合并
實(shí)際開(kāi)發(fā)中，我們經(jīng)常會(huì)通過(guò)判斷字符串的長(zhǎng)度，比如個(gè)數(shù)來(lái)實(shí)現(xiàn)換行，但是中文、英文、數(shù)字在展示的時(shí)候同樣長(zhǎng)度的字符串，其實(shí)它的寬度是不一樣的，這也是們我通俗意義上說(shuō)的寬度(像素)。
下面結(jié)合jasper套打打印業(yè)務(wù)來(lái)說(shuō)明。
1、工具類(lèi)最終版前奏
package main;
import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import javax.imageio.ImageIO;
import javax.imageio.stream.ImageOutputStream;
public class SubstringStr {
/**
* 1、自己做圖片，根據(jù)文本寬度進(jìn)行換行
*/
public void creatMyImage(String text) {
// 整體圖合成
BufferedImage bufferedImage = new BufferedImage(595, 842, BufferedImage.TYPE_INT_RGB);
// 設(shè)置圖片的背景色
Graphics2D main = bufferedImage.createGraphics();
main.fillRect(0, 0, 1500, 2600);
Graphics2D graphics2d = bufferedImage.createGraphics();
graphics2d.setColor(new Color(37, 37, 37));
Font hualaoContentFont = new Font("宋體", Font.PLAIN, 20);
graphics2d.setFont(hualaoContentFont);
graphics2d.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_GASP);
drawString1(graphics2d, text, 30, 500, 28, 71, 20, false, false, 0);
// 存儲(chǔ)到本地
String saveFilePath = "D:\\new.png";
saveImageToLocalDir(bufferedImage, saveFilePath);
}
private void saveImageToLocalDir(BufferedImage img, String saveFilePath) {
try {
//bufferedimage 轉(zhuǎn)換成 inputstream
ByteArrayOutputStream bs = new ByteArrayOutputStream();
ImageOutputStream imOut = ImageIO.createImageOutputStream(bs);
ImageIO.write(img, "jpg", imOut);
InputStream inputStream = new ByteArrayInputStream(bs.toByteArray());
long length = imOut.length();
OutputStream outStream = new FileOutputStream(saveFilePath);
//輸出流
byte[] bytes = new byte[1024];
long count = 0;
while(count < length){
int len = inputStream.read(bytes, 0, 1024);
count +=len;
outStream.write(bytes, 0, len);
}
outStream.flush();
inputStream.close();
outStream.close();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* @param graphics2d
* @param text 文本
* @param lineHeight 行高（注意字體大小的控制哦）
* @param maxWidth 行寬
* @param maxLine 最大行數(shù)
* @param left 左邊距 //整段文字的左邊距
* @param top 上邊距 //整段文字的上邊距
* @param trim 是否修剪文本（1、去除首尾空格，2、將多個(gè)換行符替換為一個(gè)）
* @param lineIndent 是否首行縮進(jìn)
*/
public static void drawString1(Graphics2D graphics2d, String text, float lineHeight, float maxWidth, int maxLine, float left,
float top, boolean trim, boolean lineIndent, int resultLine) {
if (text == null || text.length() == 0)
return;
if (trim) {
text = text.replaceAll("\\n+", "\n").trim();
System.err.println("執(zhí)行了。。。。");
}
if (lineIndent) {
text = " " + text.replaceAll("\\n", "\n ");
System.err.println("執(zhí)行了=====");
}
drawString2(graphics2d, text, lineHeight, maxWidth, maxLine, left, top, resultLine);
}
/**
*
* @param graphics2d
* @param text 文本
* @param lineHeight 行高
* @param maxWidth 行寬
* @param maxLine 最大行數(shù)
* @param left 左邊距
* @param top 上邊距
*/
private static void drawString2(Graphics2D graphics2d, String text, float lineHeight, float maxWidth, int maxLine,
float left, float top, int resultLine) {
if (text == null || text.length() == 0) {
return;
}
FontMetrics fm = graphics2d.getFontMetrics();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < text.length(); i++) {
char strChar = text.charAt(i);
sb.append(strChar);
int stringWidth = fm.stringWidth(sb.toString());
if (strChar == '\n' || stringWidth > maxWidth) {
if (strChar == '\n') {
i += 1;
System.out.println("\n字符串內(nèi)容為：" + text.substring(0, i));
}
if (maxLine > 1) {
resultLine = resultLine + 1;
System.err.println("\nif中字符串內(nèi)容為：" + text.substring(0, i));
graphics2d.drawString(text.substring(0, i), left, top);
drawString2(graphics2d, text.substring(i), lineHeight, maxWidth, maxLine - 1, left, top + lineHeight, resultLine);
} else {
System.err.println("\nelse中字符串內(nèi)容為：" + text.substring(0, i));
graphics2d.drawString(text.substring(0, i - 1) + "…", left, top);
}
return;
}
}
System.err.println("最后字符串內(nèi)容為：" + text + "===行數(shù)為：" + resultLine);
graphics2d.drawString(text, left, top);
}
public static void main(String[] args) {
String text = "111122223所以比傳統(tǒng)紙巾更環(huán)保3334441比傳統(tǒng)紙巾更環(huán)11111111111111122223所以比傳統(tǒng)紙巾更環(huán)保3334441比傳統(tǒng)紙巾"
+ System.getProperty("line.separator") + "更環(huán)66666666"+ System.getProperty("line.separator")
+ "所以比傳統(tǒng)紙巾更環(huán)保3334441比傳統(tǒng)紙巾更環(huán)。。。。。。。"
+ "111111122223所以比傳統(tǒng)紙巾更環(huán)保3334441比傳統(tǒng)紙巾更環(huán)11111111111";
SubstringStr test = new SubstringStr();
test.creatMyImage(text);
System.out.println("輸入圖片完成：D:/new.png");
}
}
2、工具類(lèi)最終版
package com.sinosoft.emr.util;
import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class SubstrUtil {
private static int index = 0;
/**
* 1、自己做圖片 ，根據(jù)文本寬度進(jìn)行換行
*/
public static Map<String, Object> creatMyImage(String text, Font font, int appointRow, Map<String, Object> map, int rows) {
index = 0;
// 整體圖合成
BufferedImage bufferedImage = new BufferedImage(595, 842, BufferedImage.TYPE_INT_RGB);
Graphics2D graphics2d = bufferedImage.createGraphics();
graphics2d.setColor(new Color(37, 37, 37));
graphics2d.setFont(font);
graphics2d.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_GASP);
map = myDrawString(graphics2d, text, 30, 500, appointRow, 71, 20, map, rows);
return map;
}
/**
* 2、根據(jù)寬度截取字符串
* @param graphics2d
* @param text 文本
* @param lineHeight 行高
* @param maxWidth 行寬
* @param maxLine 最大行數(shù)
* @param left 左邊距
* @param top 上邊距
*/
private static Map<String, Object> myDrawString(Graphics2D graphics2d, String text, int lineHeight, int maxWidth,
int maxLine, int left, int top, Map<String, Object> map, int rows) {
if (text == null || text.length() == 0) {
return map;
}
FontMetrics fm = graphics2d.getFontMetrics();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < text.length(); i++) {
char strChar = text.charAt(i);
sb.append(strChar);
int stringWidth = fm.stringWidth(sb.toString());
int strLength = text.substring(0, i).length();
if (strLength >= 53 || strChar == '\n' || stringWidth >= maxWidth) {
if (strChar == '\n') {
i += 1;
// System.out.println("字符串內(nèi)容為：" + text.substring(0, i));
}
if (maxLine > 1) {
rows = rows + 1;
// System.err.println("if中字符串內(nèi)容為：" + text.substring(0, i));
char value = ' ', value1 = ' ';
try {
value = text.substring(i).charAt(0);
value1 = text.substring(i - 1).charAt(0);
} catch (Exception e) {
/*e.printStackTrace();*/
System.err.println("----" + e.getMessage());
}
if (isChinesePunctuation(value) && checkCharCN(value1)) {
map.put("row" + rows, text.substring(0, i - 1));
myDrawString(graphics2d, text.substring(i - 1), lineHeight, maxWidth, maxLine - 1, left, top + lineHeight, map, rows);
} else {
map.put("row" + rows, text.substring(0, i));
myDrawString(graphics2d, text.substring(i), lineHeight, maxWidth, maxLine - 1, left, top + lineHeight, map, rows);
}
index = index + i;
map.put("index", index);
// System.err.println("---下標(biāo)" + index);
} else {
rows = rows + 1;
map.put("row" + rows, text.substring(0, i));
// System.err.println("else中字符串內(nèi)容為：" + text.substring(0, i));
index = index + i;
map.put("index", index);
}
return map;
}
}
return map;
}
// 2.1 判斷字符是否是中文
public static boolean checkCharCN(char c) {
String s = String.valueOf(c);
String regex = "[\u4e00-\u9fa5]";
Pattern p = Pattern.compile(regex);
Matcher m = p.matcher(s);
return m.matches();
}
// 2.2 判斷字符是否是中文標(biāo)點(diǎn)符號(hào)
public static boolean isChinesePunctuation(char c) {
Character.UnicodeBlock ub = Character.UnicodeBlock.of(c);
if (ub == Character.UnicodeBlock.GENERAL_PUNCTUATION || ub == Character.UnicodeBlock.CJK_SYMBOLS_AND_PUNCTUATION
|| ub == Character.UnicodeBlock.HALFWIDTH_AND_FULLWIDTH_FORMS
|| ub == Character.UnicodeBlock.CJK_COMPATIBILITY_FORMS
|| ub == Character.UnicodeBlock.VERTICAL_FORMS) {
return true;
} else {
return false;
}
}
/**
* 3、針對(duì)jasper中寬度較短的文本
* @author wanglong
* @date 2020年11月10日下午7:12:14
*/
public static Map<String, Object> creatShortImage(String text, Font font, int appointRow, Map<String, Object> map, int rows) {
index = 0;
// 整體圖合成
BufferedImage bufferedImage = new BufferedImage(595, 842, BufferedImage.TYPE_INT_RGB);
// 設(shè)置圖片的背景色
Graphics2D main = bufferedImage.createGraphics();
main.fillRect(0, 0, 595, 842);
Graphics2D graphics2d = bufferedImage.createGraphics();
graphics2d.setColor(new Color(37, 37, 37));
graphics2d.setFont(font);
graphics2d.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_GASP);
map = myDrawShortString(graphics2d, text, 30, 230, appointRow, 71, 20, map, rows);
return map;
}
// 3.1
private static Map<String, Object> myDrawShortString(Graphics2D graphics2d, String text, int lineHeight, int maxWidth,
int maxLine, int left, int top, Map<String, Object> map, int rows) {
if (text == null || text.length() == 0) {
return map;
}
FontMetrics fm = graphics2d.getFontMetrics();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < text.length(); i++) {
char strChar = text.charAt(i);
sb.append(strChar);
int stringWidth = fm.stringWidth(sb.toString());
if (strChar == '\n' || stringWidth > maxWidth) {
if (strChar == '\n') {
i += 1;
//System.out.println("字符串內(nèi)容為：" + text.substring(0, i));
}
if (maxLine > 1) {
rows = rows + 1;
//System.err.println("if中字符串內(nèi)容為：" + text.substring(0, i));
map.put("row" + rows, text.substring(0, i));
map.put("row_len" + rows, stringWidth);
myDrawShortString(graphics2d, text.substring(i), lineHeight, maxWidth, maxLine - 1, left, top + lineHeight, map, rows);
} else {
rows = rows + 1;
map.put("row" + rows, text.substring(0, i));
map.put("row_len" + rows, stringWidth);
//System.err.println("else中字符串內(nèi)容為：" + text.substring(0, i));
}
return map;
}
}
return map;
}
public static void main(String[] args) {
Map<String, Object> map = new LinkedHashMap<>();
int rows = 0;
int appointRow = 4;
Font font = new Font("宋體", Font.PLAIN, 12);
String text = "111122223所以比傳統(tǒng)紙巾更環(huán)保3334441比傳統(tǒng)紙巾更環(huán)11111111111111122223所以比傳統(tǒng)紙巾更環(huán)保3334441測(cè)試數(shù)據(jù)"
+ System.getProperty("line.separator") + "在仿蘋(píng)果官網(wǎng)垃圾桶時(shí)， 設(shè)計(jì)出的UI使用PingFang SC 字體"+ System.getProperty("line.separator")
+ "天津市防控指揮部消息稱(chēng),經(jīng)排查,濱海新區(qū)中新天津紙巾更環(huán)保3334441比傳統(tǒng)紙巾更環(huán)666所以比傳統(tǒng)紙巾更環(huán)保3334441比傳統(tǒng)紙巾更環(huán)8888";
int length = text.length();
map = creatMyImage(text, font, appointRow, map, rows);
if (length > index) {
System.out.println("還剩余文本：" + text.substring(index));
}
System.out.println("\n<<--->>>rows=" + rows + ", map="+map);
}
}
說(shuō)明：此工具類(lèi)我們經(jīng)理進(jìn)行了改造，生成的文本內(nèi)容符合中國(guó)人的書(shū)寫(xiě)習(xí)慣：行首不能是標(biāo)點(diǎn)符號(hào)。如果行首是標(biāo)點(diǎn)符號(hào)，上一行的最后一個(gè)文字會(huì)挪至本行。
3、項(xiàng)目中具體使用
3.1 controller層
/**
* 4、打印 病程記錄
* @author wanglong
* @date 2020年3月4日 下午5:22:57
*/
@RequestMapping(value = "printEmrCourse", method = RequestMethod.GET, produces = MediaType.APPLICATION_PDF_VALUE)
public void printEmrCourse(@RequestParam(value = "id", required = true) String id,
@RequestParam(value = "courseType", required = true) String courseType,
@RequestParam(value = "token", required = true) String token, HttpServletResponse response) {
List<String> filePathList = new ArrayList<String>();
Map<String, Map<String, Object>> map = iEmrCourseSelectBusi.selectEmrCourseData(id, courseType, token);
try {
if (map.size() > 0) {
for (int i = 0, len = map.size(); i < len; i++) {
if (i % 2 == 0) {
String path1 = iEmrCourseSelectBusi.getCoursePdf(map.get("map" + i), "emrCourseLeft.jasper");
if (!"".equals(path1)) {
filePathList.add(path1);
}
} else {
String path2 = iEmrCourseSelectBusi.getCoursePdf(map.get("map" + i), "emrCourseRight.jasper");
if (!"".equals(path2)) {
filePathList.add(path2);
}
}
}
iEmrCourseSelectBusi.printEmrCoursePdf(filePathList, response);
}
} catch (Exception e) {
e.printStackTrace();
}
}
3.2 serviceImpl層
@Service("iEmrCourseSelectBusi")
public class EmrCourseBusiSelectImpl extends EmrCourseSelectServiceImpl implements IEmrCourseSelectBusi{
private static final long serialVersionUID = 1L;
private Font font = new Font("宋體", Font.PLAIN, 12);
// 讀取配置文件里的jasper路徑
@Value("${jasperPath}")
private String jasperPath;
/**
* 4、打印 病程記錄
* @author wanglong
* @date 2020年11月9日下午3:49:23
*/
@Override
public Map<String, Map<String, Object>> selectEmrCourseData(String id, String courseType, String token) {
Map<String, Map<String, Object>> resultMap = new LinkedHashMap<>();
Map<String, Object> map = new LinkedHashMap<>();
int rows = 0, appointRow = 28;
StringBuffer bufferStr = new StringBuffer();
String lineBreak = System.getProperty("line.separator"); // 換行符
try {
EmrCourse record = emrCourseMapper.selectByPrimaryKey(id);
if (record != null) {
map.put("patientName", record.getPatientName());
map.put("fkHosRegisterHosNo", record.getFkHosRegisterHosNo());
String recordTime = DateUtil.dateToString(record.getCourseRecordTime(), "yyyy-MM-dd HH:mm");
String doctorName = record.getDoctorRealName();
if ("1".equals(courseType)) {
bufferStr.append(recordTime + lineBreak);
String tempStr = record.getGeneralRecords() == null ? "" : record.getGeneralRecords();
String blankStr = "";
if (!"".equals(tempStr)) {
blankStr = StringDealUtil.getSubString(blankStr, tempStr);
}
String generalRecords = record.getGeneralRecords() == null ? "" : (blankStr + lineBreak);
bufferStr.append(generalRecords);
}
String updateName = record.getUpdateOprName();
String opraterName = updateName == null ? record.getAddOprName() : updateName;
bufferStr.append("\t\t\t\t\t\t\t\t\t簽 名：" + opraterName + lineBreak);
String text = bufferStr.toString();
int length = text.length();
map = SubstrUtil.creatMyImage(text, font, appointRow, map, rows);
map.put("pageNum", "1");
resultMap.put("map0", map);
int index = (int) map.get("index");
if (length > index) {
String _text = StringDealUtil.getSurplusText(text, index);
resultMap = this.getOtherMap(_text, appointRow, resultMap, 1);
}
}
} catch (Exception e) {
e.printStackTrace();
}
return resultMap;
}
// 4.1 截取文本獲取其余map
private Map<String, Map<String, Object>> getOtherMap(String text, int appointRow,
Map<String, Map<String, Object>> resultMap, int i) {
int length = text.length();
Map<String, Object> map = new LinkedHashMap<>();
map = SubstrUtil.creatMyImage(text, font, appointRow, map, 0);
map.put("pageNum", i + 1 + "");
resultMap.put("map"+ i, map);
int index = (int) map.get("index");
if (length > index) {
String _text = StringDealUtil.getSurplusText(text, index);
resultMap = this.getOtherMap(_text, appointRow, resultMap, i+1);
}
return resultMap;
}
/**
* 5、生成pdf
* @author wanglong
* @date 2020年11月9日下午1:52:42
*/
@Override
public String getCoursePdf(Map<String, Object> map, String jasperName) {
String fileInfo = "";
Instant timestamp = Instant.now();
try {
JRDataSource jrDataSource = new JRBeanCollectionDataSource(null);
File reportFile = new File(jasperPath + jasperName);
String exportFileName = timestamp.toEpochMilli() + ".pdf";
fileInfo = jasperPath + exportFileName;
//調(diào)用工具類(lèi)
JasperHelper.exportPdf2File(jasperPath + exportFileName, reportFile, map, jrDataSource);
} catch (Exception e) {
e.printStackTrace();
}
return fileInfo;
}
/**
* 5.1 合成pdf進(jìn)行打印
* @author wanglong
* @date 2020年11月9日下午1:52:58
*/
@Override
public void printEmrCoursePdf(List<String> filePathList, HttpServletResponse response) {
List<File> files = new ArrayList<File>();
try {
if (filePathList != null && filePathList.size() > 0) {
for (int i = 0, length = filePathList.size(); i < length; i++) {
String pathName = filePathList.get(i);
files.add(new File(pathName));
}
String newFileName = Instant.now().toEpochMilli() + "病程記錄mul2one.pdf";
String targetPath = jasperPath + newFileName;
File newFile = PdfMergeUtil.mulFile2One(files, targetPath);
if (newFile.exists()) {
// 先將單個(gè)的pdf文件刪除
for (File file : files) {
if (file.exists() && file.isFile()) {
file.delete();
}
}
newFile.getName();
PdfUtil.downloadFile(response, targetPath, newFileName);
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
4、工具類(lèi)補(bǔ)充
package utils;
import net.sf.jasperreports.engine.*;
import net.sf.jasperreports.engine.util.JRLoader;
import java.io.*;
import java.util.Map;
public class JasperHelper {
/**
* 1、直接導(dǎo)出pdf文件
* @author wanglong
* @date 2020年10月31日下午9:10:41
*/
public static void exportPdf2File(String defaultFilename, File is, Map<String, Object> parameters, JRDataSource conn) {
try {
JasperReport jasperReport = (JasperReport) JRLoader.loadObject(is);
JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, parameters, conn);
exportPdfToFile(jasperPrint, defaultFilename);
} catch (Exception e) {
e.printStackTrace();
}
}
// 1.1 導(dǎo)出Pdf
private static void exportPdfToFile(JasperPrint jasperPrint, String defaultFilename) throws IOException, JRException {
FileOutputStream ouputStream = new FileOutputStream(new File(defaultFilename));
JasperExportManager.exportReportToPdfStream(jasperPrint, ouputStream);
ouputStream.flush();
ouputStream.close();
}
}
package utils;
import java.io.File;
import java.io.IOException;
import java.util.List;
import org.apache.pdfbox.io.MemoryUsageSetting;
import org.apache.pdfbox.multipdf.PDFMergerUtility;
/**
* @name: PdfMergeUtil
* @Description: pdf合并拼接工具類(lèi)
* @author wanglong
* @date 2020年2月25日下午4:33:13
* @version 1.0
*/
public class PdfMergeUtil {
/**
* @Description: pdf合并拼接
* @param files 文件列表
* @param targetPath 合并到
* @throws IOException
*/
public static File mulFile2One(List<File> files,String targetPath) throws IOException{
// pdf合并工具類(lèi)
PDFMergerUtility mergePdf = new PDFMergerUtility();
for (File f : files) {
if(f.exists() && f.isFile()){
// 循環(huán)添加要合并的pdf
mergePdf.addSource(f);
}
}
// 設(shè)置合并生成pdf文件名稱(chēng)
mergePdf.setDestinationFileName(targetPath);
// 合并pdf
mergePdf.mergeDocuments(MemoryUsageSetting.setupMainMemoryOnly());
return new File(targetPath);
}
}
package utils;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
/**
* 導(dǎo)出PDF
*/
public class PdfUtil {
// 下載
public static void downloadFile(HttpServletResponse response, String filePath, String fileName) {
if (fileName != null) {
response.reset();
response.setContentType("application/pdf");
// 設(shè)置文件路徑
File file = new File(filePath);
if (file.exists()) {
byte[] buffer = new byte[1024];
FileInputStream fis = null;
BufferedInputStream bis = null;
try {
fis = new FileInputStream(file);
bis = new BufferedInputStream(fis);
OutputStream os = response.getOutputStream();
int i = bis.read(buffer);
while (i != -1) {
os.write(buffer, 0, i);
i = bis.read(buffer);
}
System.out.println("download success!");
} catch (Exception e) {
e.printStackTrace();
} finally {
if (bis != null) {
try {
bis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (fis != null) {
try {
fis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
file.delete();
}
}
}
}
以上為個(gè)人經(jīng)驗(yàn)，希望能給大家一個(gè)參考，也希望大家多多支持腳本之家。
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