【经典】通过Java把Excel，Word，PDF，PPT，JPG，MP3等等文件转化为二进制格式存储到数据库

          使用Java把Excel，Word，PDF，PPT，JPG，MP4等等文件转化为二进制格式存储到数据库中，然后在需要使用的地方再还原文件即可，这样方法相比普通上传下载文件来说比较安全很多

转化文件需要用到的jar包：https://download.csdn.net/download/zxwu_1993/12058241

本地测试文件

存到数据库后的效果图

文件恢复

 

 数据库结构信息

-- Create table
create table T_AUDIT_FILE
(
  id          VARCHAR2(50) not null,
  fileid      VARCHAR2(50),
  filename    VARCHAR2(200),
  filecontent BLOB,
  filesize    INTEGER,
  suffix      VARCHAR2(50)
)


-- Add comments to the table 
comment on table T_AUDIT_FILE
  is '文件表';
-- Add comments to the columns 
comment on column T_AUDIT_FILE.id
  is 'id';
comment on column T_AUDIT_FILE.fileid
  is '文件编号';
comment on column T_AUDIT_FILE.filename
  is '文件名称';
comment on column T_AUDIT_FILE.filecontent
  is '文件内容';
comment on column T_AUDIT_FILE.filesize
  is '文件大小';
comment on column T_AUDIT_FILE.suffix
  is '文件后缀';
-- Create/Recreate primary, unique and foreign key constraints 
alter table T_AUDIT_FILE
  add constraint PK_T_AUDIT_FILE primary key (ID)

具体实现代码如下

数据库连接类

import java.sql.Connection;

import java.sql.DriverManager;

public class DBConnection {

	public static Connection getDBConnection() throws Exception {

		Connection con = null;
		String driver = "oracle.jdbc.driver.OracleDriver";
		String url = "jdbc:oracle:thin:@127.0.0.1:1521/orcl";
		String user = "ceshi";
		String password = "Ceshi_0123";
		Class.forName(driver);
		con = DriverManager.getConnection(url, user, password);
		return con;

	}

	public static void main(String[] args) throws Exception {
		getDBConnection();
		System.out.println("连接成功！");
	}
}

文件转化二进制并存储到数据库的核心实现类

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Blob;
import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.UUID;


import oracle.sql.BLOB;

@SuppressWarnings("deprecation")
public class Bolb_test {

	public static void main(String[] args) throws SQLException {
		ArrayList listFileName = new ArrayList();
		getAllFileName("D:\\pdf\\", listFileName);
		daor(listFileName);
	}

	public static void daor(ArrayList listFileName) throws SQLException {
		Connection con = null;
		long start = System.currentTimeMillis(); // count runtime
		CallableStatement pstmt = null;
		InputStream fin = null;
		OutputStream outStream = null;
		for (String path : listFileName) {
			File file = new File(path);
			try {
				con = DBConnection.getDBConnection();
				con.setAutoCommit(false);
				String sql = "insert into T_AUDIT_FILE values(?,?,?,?,?,?)";
				// insert database
				pstmt = con.prepareCall(sql);
				String docid = "";
				if (file.getName().indexOf(".", 1) == file.getName().lastIndexOf(".")) {
					docid = file.getName().substring(0, file.getName().lastIndexOf("."));
				} else {
					docid = file.getName().substring(file.getName().indexOf(".", 1) + 1,
							file.getName().lastIndexOf("."));
				}
				String suffix = file.getName().substring(file.getName().lastIndexOf(".") + 1);
				String id = UUID.randomUUID().toString().replace("-", "");
				pstmt.setString(1, id);
				pstmt.setString(2, docid);
				pstmt.setString(3, file.getName());
				Blob doccontent = BLOB.empty_lob();
				pstmt.setBlob(4, doccontent);
				pstmt.setInt(5, (int) file.length());
				pstmt.setString(6, suffix);
				pstmt.execute();
				Statement stmt = con.createStatement();
				ResultSet rs = stmt
						.executeQuery("select id,filecontent from T_AUDIT_FILE where id = '" + id + "' for update");
				// get specially columns and rows for update
				BLOB blob = null;
				while (rs.next()) {
					blob = (BLOB) rs.getBlob("filecontent");
					outStream = blob.getBinaryOutputStream();
					fin = new FileInputStream(file); // put file into stream

					// BufferedInputStream bis = new BufferedInputStream(fin);
					// byte[] b = new byte[(int) file.length()];

					// byte[] b = new byte[blob.getBufferSize()];
					int len = 0;
					while ((len = fin.read()) != -1) {
						outStream.write(len);
					}
					fin.close();
					outStream.flush();
					outStream.close();
				}
				String writeSql = "update T_AUDIT_FILE set filecontent = ? where id = ?";
				java.sql.PreparedStatement ps = con.prepareStatement(writeSql);
				ps.setBlob(1, blob);
				ps.setString(2, id);
				ResultSet rs1 = ps.executeQuery();
				rs1.close();
				con.commit();

			} catch (Exception e) {
				e.printStackTrace();
			}
		}
		con.close();
		long end = System.currentTimeMillis();
		System.out.println(end - start);
	}

	public static void getAllFileName(String path, ArrayList listFileName) {
		File file = new File(path);
		File[] files = file.listFiles();
		String[] names = file.list();
		if (names != null) {
			String[] completNames = new String[names.length];
			for (int i = 0; i < names.length; i++) {
				completNames[i] = path + names[i];
			}
			listFileName.addAll(Arrays.asList(completNames));
		}
		for (File a : files) {
			if (a.isDirectory()) {// 如果文件夹下有子文件夹，获取子文件夹下的所有文件全路径。
				getAllFileName(a.getAbsolutePath() + "\\", listFileName);
			}
		}
	}
}

文件恢复实现类

import java.io.*;
import java.sql.*;
import oracle.sql.BLOB;

@SuppressWarnings("deprecation")
public class Getbolb_test {

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

		Connection con = null;

		long start = System.currentTimeMillis(); // count runtime

		String path = "D:\\pdf\\文件恢复.jpg";

		File file = new File(path);

		try {

			con = DBConnection.getDBConnection();

			con.setAutoCommit(false);

			Statement stmt = con.createStatement();

			ResultSet rs = stmt.executeQuery("select id,filename,filecontent,filesize from T_AUDIT_FILE where id='4bde107e-9cc5-46a5-949c-65374a2bfe03'");

			// get blob form your table

			if (rs.next()) {
				
				int docsize = rs.getInt("filesize");
				String docname = rs.getString("filename");
				BLOB blob = (BLOB) rs.getBlob("filecontent");

				// get word column

				FileOutputStream output = new FileOutputStream(file);

				// define a file output stream

				InputStream input = blob.getBinaryStream();// put blob into input

				//byte[] buffer = new byte[blob.getBufferSize()];
				
				byte[] buffer = new byte[docsize];

				// if use 1024 it will lose some bytes

				int len = 0;

				while ((len = input.read(buffer)) != -1) {

					// get all input stream into output file stream

					output.write(buffer, 0, len);

					input.close();

					output.flush();

					output.close();

				}

				System.out.print("\ndownload ok\n");

			}

		}

		catch (Exception e) {

			e.printStackTrace();

		}

		con.close();

		long end = System.currentTimeMillis();

		System.out.println(end - start);

	}

}