java实现将文件(包含word，excel，图片等)转PDF

1、下载开源工具LibreOffice，可选择window和linux，这里我选择的是（LibreOffice_5.3.7_Win_x64.msi）
2、按照提示安装好后，配置环境变量path，值为”..\LibreOffice 5\program”
3、编写java代码：
3.1、CommandResult .java:

import java.io.IOException;
import java.util.Iterator;
import java.util.List;

/**
 * 描述：执行命令返回值
 *
 * @author ssl
 * @create 2017/12/12 11:05
 */
public class CommandResult {
    int ret = 0;
    List<String> outLines;
    List<String> errLines;
    IOException exception;
    String command;

    public CommandResult() {
    }

    public int getRet() {
        return this.ret;
    }

    public void setRet(int ret) {
        this.ret = ret;
    }

    public List<String> getOutLines() {
        return this.outLines;
    }

    public void setOutLines(List<String> outLines) {
        this.outLines = outLines;
    }

    public List<String> getErrLines() {
        return this.errLines;
    }

    public void setErrLines(List<String> errLines) {
        this.errLines = errLines;
    }

    public IOException getIOException() {
        return this.exception;
    }

    public void setIOException(IOException exception) {
        this.exception = exception;
    }

    public String getCommand() {
        return this.command;
    }

    public void setCommand(String command) {
        this.command = command;
    }

    public String getOutput() {
        StringBuffer output = new StringBuffer();
        Iterator var2 = this.outLines.iterator();

        String line;
        while (var2.hasNext()) {
            line = (String) var2.next();
            if (trimToNull(line) != null) {
                output.append(line).append("\r\n");
            }
        }

        var2 = this.errLines.iterator();

        while (var2.hasNext()) {
            line = (String) var2.next();
            if (trimToNull(line) != null) {
                output.append(line).append("\r\n");
            }
        }

        return output.toString();
    }

    public static String trimToNull(String str) {
        String ts = trim(str);
        return isEmpty(ts) ? null : ts;
    }

    public static String trim(String str) {
        return str == null ? null : str.trim();
    }

    public static boolean isEmpty(String str) {
        return str == null || str.length() == 0;
    }
}

3.2、CommandUtils.java:

import org.apache.commons.io.IOUtils;

import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * 描述：执行命令行工具类
 *
 * @author ssl
 * @create 2017/12/12 11:05
 */
public class CommandUtils {
    static Pattern p = Pattern.compile("error=(\\d+),");

    public CommandUtils() {
    }

    public static CommandResult execute(String... args) {
        CommandResult commandResult = new CommandResult();
        StringBuffer cmd = new StringBuffer();
        for (int i = 0; i < args.length; ++i) {
            if (i == 0) {
                cmd.append(args[i]);
            } else {
                cmd.append(" ").append(args[i]);
            }
        }
        commandResult.setCommand(cmd.toString());
        Process process = null;
        try {
            process = (new ProcessBuilder(args)).start();
        } catch (IOException var8) {
            Matcher m = p.matcher(var8.getMessage());
            if (m.find()) {
                commandResult.setRet(Integer.valueOf(m.group(1)).intValue());
                commandResult.setIOException(var8);
            } else {
                commandResult.setRet(-1);
                commandResult.setIOException(var8);
            }

            return commandResult;
        }

        try {
            commandResult.setOutLines(IOUtils.readLines(process.getInputStream()));
            commandResult.setErrLines(IOUtils.readLines(process.getErrorStream()));
            return commandResult;
        } catch (IOException var7) {
            commandResult.setRet(-1);
            commandResult.setIOException(var7);
            return commandResult;
        }
    }
}

3.3、PdfUtils.java,该类需要依赖commons-io、commons-lang3工具包

import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.SystemUtils;

import java.io.*;
import java.util.UUID;

/**
 * 描述：pdf工具类
 *
 * @author ssl
 * @create 2017/12/12 11:09
 */
public class PdfUtils {

    public static byte[] fileToPdf(String docPath) throws Exception {
        byte[] docBuf = IOUtils.toByteArray(new FileInputStream(docPath));
        return fileToPdf(docBuf);
    }

    public static byte[] fileToPdf(byte[] docBuf) throws Exception {
        byte[] pdfBuf = null;
        File tempDirectory = new File(System.getProperty("java.io.tmpdir"));
        String fileName = UUID.randomUUID().toString();
        File fileDoc = new File(tempDirectory.getAbsolutePath() + File.separator + fileName + ".doc");
        File filePdf = new File(tempDirectory.getAbsolutePath() + File.separator + fileName + ".pdf");
        System.out.println(filePdf.getPath());
        IOUtils.write(docBuf, new FileOutputStream(fileDoc));
        String command = "soffice";
        if (SystemUtils.IS_OS_MAC_OSX) {
            command = "/Applications/LibreOffice.app/Contents/MacOS/soffice";
        } else if (SystemUtils.IS_OS_WINDOWS) {
            command = "soffice";
        }
        CommandResult commandResult = CommandUtils.execute(command, "--headless", "--convert-to",
                "pdf:writer_pdf_Export", "--outdir", System.getProperty("java.io.tmpdir"),
                fileDoc.getAbsolutePath());
        if (commandResult.getRet() == 0) {
            if (filePdf.exists() && filePdf.length() > 0) {
                pdfBuf = new byte[(int) filePdf.length()];
                IOUtils.readFully(new FileInputStream(filePdf), pdfBuf);
                // 删除临时文件
                FileWriter fw;
                try {
                    fw = new FileWriter(fileDoc);
                    fw.write("");
                    fw.close();
                    fileDoc.delete();

                    fw = new FileWriter(filePdf);
                    fw.write("");
                    fw.close();
                    filePdf.delete();
                } catch (Exception e) {
                    e.printStackTrace();
                }
                return pdfBuf;
            } else {
                String output = commandResult.getOutput();
                System.out.println(commandResult.getCommand() + "\r\n" + output);
                throw new IOException(output);
            }
        } else {
            System.out.println(commandResult.getIOException());
            throw commandResult.getIOException();
        }
    }

    /**
     * 文件(word，excel，图片等)转pdf
     *
     * @param filePath 文件完整路径(包含文件名),eg:<br>c:/file/doc/1.doc
     * @param pdfPath  存放pdf文件的路径,eg:<br>c:/file/pdf
     * @return
     * @throws IOException
     */
    public static String fileToPdf(String filePath, String pdfPath) throws IOException {
        /** 获取文件名 */
        File file = new File(filePath);
        String fileName = FilenameUtils.getBaseName(filePath) + ".pdf";
        File pdfFile = new File(pdfPath, fileName);
        /** 定义执行命令语句 */
        String command = "soffice";
        if (SystemUtils.IS_OS_MAC_OSX) {
            command = "/Applications/LibreOffice.app/Contents/MacOS/soffice";
        } else if (SystemUtils.IS_OS_WINDOWS) {
            command = "soffice";
        }
        CommandResult commandResult = CommandUtils.execute(command, "--headless", "--convert-to",
                "pdf:writer_pdf_Export", "--outdir", pdfPath, file.getAbsolutePath());
        if (commandResult.getRet() == 0) {
            if (pdfFile.exists() && pdfFile.length() > 0) {
                /** 转为pdf成功 */
                return pdfFile.getPath();
            } else {
                String output = commandResult.getOutput();
                System.out.println(commandResult.getCommand() + "\r\n" + output);
                throw new IOException(output);
            }
        } else {
            System.out.println(commandResult.getIOException());
            throw commandResult.getIOException();
        }
    }

    public static void main(String[] args) {
        String filePath = "F:\\libreoffice\\file\\1.doc";
        String pdfPath = "F:\\libreoffice\\file";
        try {
            pdfPath = fileToPdf(filePath, pdfPath);
            System.out.println(pdfPath);
            //注意，下面方法有可能会执行不成功的，原因是生成文件和pdf的目录系统不允许写入，
            //所以一般还是手动设置好文件和pdf目录
            //byte[] pdfbuf = fileToPdf(filePath);
            //FileUtils.writeByteArrayToFile(new File("C:\\Users\\49383\\Desktop\\工作\\pp22.pdf"), pdfbuf);
            System.out.println("success!");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

注意：执行不成功时候，最好是将执行的cmd命令复制出来，指定一个可写入的目录，在cmd窗口进行调试，还可以查看soffice的帮助说明：soffice –help