Java 字符串根据宽度(像素)换行
在一些场景下，我们经常会通过判断字符串的长度，比如个数来实现换行，但是中文、英文、数字、其实在展示的时候同样长度的字符串，其实它的宽度是不一样的，这也是们我通俗意义上说的宽度(像素)
根据像素宽度进行换行
需求：
/**
* 10、自己做图片 ，根据文本宽度进行换行
*/
@Test
public void creatMyImage(){
//整体图合成
BufferedImage bufferedImage = new BufferedImage(500, 500, BufferedImage.TYPE_INT_RGB);
//设置图片的背景色
Graphics2D main = bufferedImage.createGraphics();
main.fillRect(0, 0, 500, 500);
String text = "111122223所以比传统纸巾更环保3334441比传统纸巾更环11111111111111122223所以比传统纸巾更环保3334441比传统纸巾更环11111111111111122223所以比传统纸巾更环保3334441比传统纸巾更环11111111111111122223所以比传统纸巾更环保3334441比传统纸巾更环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);
//存储到本地
String saveFilePath = "/Users/healerjean/Desktop/new.png";
saveImageToLocalDir(bufferedImage, saveFilePath);
}
/**
*
* @param g
* @param text 文本
* @param lineHeight 行高（注意字体大小的控制哦）
* @param maxWidth 行宽
* @param maxLine 最大行数
* @param left 左边距 //整段文字的左边距
* @param top 上边距 //整顿文字的上边距
* @param trim 是否修剪文本（1、去除首尾空格，2、将多个换行符替换为一个）
* @param lineIndent 是否首行缩进
*/
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 行宽
* @param maxLine 最大行数
* @param left 左边距
* @param top 上边距
*/
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字符串根据宽度(像素)进行换行及Pdf合并
实际开发中，我们经常会通过判断字符串的长度，比如个数来实现换行，但是中文、英文、数字在展示的时候同样长度的字符串，其实它的宽度是不一样的，这也是们我通俗意义上说的宽度(像素)。
下面结合jasper套打打印业务来说明。
1、工具类最终版前奏
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、自己做图片，根据文本宽度进行换行
*/
public void creatMyImage(String text) {
// 整体图合成
BufferedImage bufferedImage = new BufferedImage(595, 842, BufferedImage.TYPE_INT_RGB);
// 设置图片的背景色
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("宋体", 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);
// 存储到本地
String saveFilePath = "D:\\new.png";
saveImageToLocalDir(bufferedImage, saveFilePath);
}
private void saveImageToLocalDir(BufferedImage img, String saveFilePath) {
try {
//bufferedimage 转换成 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);
//输出流
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（注意字体大小的控制哦）
* @param maxWidth 行宽
* @param maxLine 最大行数
* @param left 左边距 //整段文字的左边距
* @param top 上边距 //整段文字的上边距
* @param trim 是否修剪文本（1、去除首尾空格，2、将多个换行符替换为一个）
* @param lineIndent 是否首行缩进
*/
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("执行了。。。。");
}
if (lineIndent) {
text = " " + text.replaceAll("\\n", "\n ");
System.err.println("执行了=====");
}
drawString2(graphics2d, text, lineHeight, maxWidth, maxLine, left, top, resultLine);
}
/**
*
* @param graphics2d
* @param text 文本
* @param lineHeight 行高
* @param maxWidth 行宽
* @param maxLine 最大行数
* @param left 左边距
* @param top 上边距
*/
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字符串内容为：" + text.substring(0, i));
}
if (maxLine > 1) {
resultLine = resultLine + 1;
System.err.println("\nif中字符串内容为：" + 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中字符串内容为：" + text.substring(0, i));
graphics2d.drawString(text.substring(0, i - 1) + "…", left, top);
}
return;
}
}
System.err.println("最后字符串内容为：" + text + "===行数为：" + resultLine);
graphics2d.drawString(text, left, top);
}
public static void main(String[] args) {
String text = "111122223所以比传统纸巾更环保3334441比传统纸巾更环11111111111111122223所以比传统纸巾更环保3334441比传统纸巾"
+ System.getProperty("line.separator") + "更环66666666"+ System.getProperty("line.separator")
+ "所以比传统纸巾更环保3334441比传统纸巾更环。。。。。。。"
+ "111111122223所以比传统纸巾更环保3334441比传统纸巾更环11111111111";
SubstringStr test = new SubstringStr();
test.creatMyImage(text);
System.out.println("输入图片完成：D:/new.png");
}
}
2、工具类最终版
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、自己做图片 ，根据文本宽度进行换行
*/
public static Map<String, Object> creatMyImage(String text, Font font, int appointRow, Map<String, Object> map, int rows) {
index = 0;
// 整体图合成
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、根据宽度截取字符串
* @param graphics2d
* @param text 文本
* @param lineHeight 行高
* @param maxWidth 行宽
* @param maxLine 最大行数
* @param left 左边距
* @param top 上边距
*/
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("字符串内容为：" + text.substring(0, i));
}
if (maxLine > 1) {
rows = rows + 1;
// System.err.println("if中字符串内容为：" + 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("---下标" + index);
} else {
rows = rows + 1;
map.put("row" + rows, text.substring(0, i));
// System.err.println("else中字符串内容为：" + text.substring(0, i));
index = index + i;
map.put("index", index);
}
return map;
}
}
return map;
}
// 2.1 判断字符是否是中文
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 判断字符是否是中文标点符号
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、针对jasper中宽度较短的文本
* @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;
// 整体图合成
BufferedImage bufferedImage = new BufferedImage(595, 842, BufferedImage.TYPE_INT_RGB);
// 设置图片的背景色
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("字符串内容为：" + text.substring(0, i));
}
if (maxLine > 1) {
rows = rows + 1;
//System.err.println("if中字符串内容为：" + 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中字符串内容为：" + 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("宋体", Font.PLAIN, 12);
String text = "111122223所以比传统纸巾更环保3334441比传统纸巾更环11111111111111122223所以比传统纸巾更环保3334441测试数据"
+ System.getProperty("line.separator") + "在仿苹果官网垃圾桶时， 设计出的UI使用PingFang SC 字体"+ System.getProperty("line.separator")
+ "天津市防控指挥部消息称,经排查,滨海新区中新天津纸巾更环保3334441比传统纸巾更环666所以比传统纸巾更环保3334441比传统纸巾更环8888";
int length = text.length();
map = creatMyImage(text, font, appointRow, map, rows);
if (length > index) {
System.out.println("还剩余文本：" + text.substring(index));
}
System.out.println("\n<<--->>>rows=" + rows + ", map="+map);
}
}
说明：此工具类我们经理进行了改造，生成的文本内容符合中国人的书写习惯：行首不能是标点符号。如果行首是标点符号，上一行的最后一个文字会挪至本行。
3、项目中具体使用
3.1 controller层
/**
* 4、打印 病程记录
* @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层
@Service("iEmrCourseSelectBusi")
public class EmrCourseBusiSelectImpl extends EmrCourseSelectServiceImpl implements IEmrCourseSelectBusi{
private static final long serialVersionUID = 1L;
private Font font = new Font("宋体", Font.PLAIN, 12);
// 读取配置文件里的jasper路径
@Value("${jasperPath}")
private String jasperPath;
/**
* 4、打印 病程记录
* @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"); // 换行符
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签 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 截取文本获取其余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;
//调用工具类
JasperHelper.exportPdf2File(jasperPath + exportFileName, reportFile, map, jrDataSource);
} catch (Exception e) {
e.printStackTrace();
}
return fileInfo;
}
/**
* 5.1 合成pdf进行打印
* @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() + "病程记录mul2one.pdf";
String targetPath = jasperPath + newFileName;
File newFile = PdfMergeUtil.mulFile2One(files, targetPath);
if (newFile.exists()) {
// 先将单个的pdf文件删除
for (File file : files) {
if (file.exists() && file.isFile()) {
file.delete();
}
}
newFile.getName();
PdfUtil.downloadFile(response, targetPath, newFileName);
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
4、工具类补充
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、直接导出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 导出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合并拼接工具类
* @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合并工具类
PDFMergerUtility mergePdf = new PDFMergerUtility();
for (File f : files) {
if(f.exists() && f.isFile()){
// 循环添加要合并的pdf
mergePdf.addSource(f);
}
}
// 设置合并生成pdf文件名称
mergePdf.setDestinationFileName(targetPath);
// 合并pdf
mergePdf.mergeDocuments(MemoryUsageSetting.setupMainMemoryOnly());
return new File(targetPath);
}
}
package utils;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
/**
* 导出PDF
*/
public class PdfUtil {
// 下载
public static void downloadFile(HttpServletResponse response, String filePath, String fileName) {
if (fileName != null) {
response.reset();
response.setContentType("application/pdf");
// 设置文件路径
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();
}
}
}
}
以上为个人经验，希望能给大家一个参考，也希望大家多多支持服务器之家。
原文链接：https://blog.csdn.net/u012954706/article/details/81511216