postgresql数据库保存和下载二进制文件的几种方式

概述           前序：如标题所示，主要是贴核心代码。基本能用。都可以用的，我亲测过了。 //方式一：将文件转成字节数组，采用原生sql存到数据库if(StringUtils.isNotEmpty(multipartFile.getOriginalFilename())) { //获取file文件 CommonsMultipartFile cmf = (CommonsMultipartF

前序：如标题所示，主要是贴核心代码。基本能用。都可以用的，我亲测过了。

//方式一：将文件转成字节数组，采用原生sql存到数据库if(StringUtils.isNotEmpty(multipartfile.getoriginalfilename())) {	//获取file文件	Commonsmultipartfile cmf = (Commonsmultipartfile) multipartfile;	diskfileItem dfi = (diskfileItem)cmf.getfileItem();	file file = dfi.getStoreLocation();	//转成流    inputStream ips = new fileinputStream(file);    	byte[] byteData = new byte[(int) file.length()];	ips.read(byteData,byteData.length);	    DataSource ds = this.jdbcTemplate.getDataSource();	Connection conn = ds.getConnection();	String sql = "update tpm_plan set attachment = ? where ID = ?";	PreparedStatement ps = conn.prepareStatement(sql);	ps.setBytes(1,byteData);	ps.setLong(2,69);    int i=ps.executeUpdate();    if(i==0){        Boolean flag=false;        System.out.println(flag);    }	DataSourceUtils.releaseConnection(conn,ds);}//方式二：采用原生sql存二进制文件if(StringUtils.isNotEmpty(multipartfile.getoriginalfilename())) {	//获取file文件	Commonsmultipartfile cmf = (Commonsmultipartfile) multipartfile;	diskfileItem dfi = (diskfileItem)cmf.getfileItem();	file file = dfi.getStoreLocation();	//转成流    inputStream ips = new fileinputStream(file);	    DataSource ds = this.jdbcTemplate.getDataSource();	Connection conn = ds.getConnection();	String sql = "update tpm_plan set attachment = ? where ID = ?";	PreparedStatement ps = conn.prepareStatement(sql);    ps.setBinaryStream(1,ips,file.length());	ps.setLong(2,ds);}//方式三：通过实体存二进制数据if(StringUtils.isNotEmpty(multipartfile.getoriginalfilename())) {	//获取file文件	Commonsmultipartfile cmf = (Commonsmultipartfile) multipartfile;	diskfileItem dfi = (diskfileItem)cmf.getfileItem();	file file = dfi.getStoreLocation();	//转成流    inputStream ips = new fileinputStream(file);    //转成字节数组	byte[] byteData = new byte[(int) file.length()];	ips.read(byteData,byteData.length);		PrePlan p = new PrePlan();	p.setAttachment(byteData);	//保存实体	}//原生sql方式取二进制数据，转成文件if(true) {    DataSource ds = this.jdbcTemplate.getDataSource();	Connection conn = ds.getConnection();	Statement  stmt = conn.createStatement();    String sql = "select attachment from tpm_plan where ID = 40";    ResultSet  rs = stmt.executequery(sql);    while (rs.next()){        OutputStream ops = null;        inputStream ips = null;        file file = new file("d:" + file.separator + "11.docx");        try {           ips = rs.getBinaryStream(1);           byte[] buffer = new byte[ips.available()];//or other value like 1024           ops = new fileOutputStream(file);           for (int i; (i = ips.read(buffer)) > 0;)           {                ops.write(buffer,i);                ops.flush();           }        }        catch (Exception ex){            ex.printstacktrace(System.out);        }        finally {            ips.close();            ops.close();        }    }}//实体方式取二进制数据,转成文件if(true) {	String sql = "from tpm_plan where ID='" + 69+"'";		PrePlan p = new PrePlan();    OutputStream ops = null;	try {		p = getPrePlanByID((long)69);		file file = new file("d:" + file.separator + "12.docx");        try {		                              byte[] buffer = new byte[1024];//or other value like 1024           ops = new fileOutputStream(file);           bufferedoutputstream  stream = new bufferedoutputstream(ops);           stream.write(p.getAttachment());         } catch (Exception ex) {        ex.printstacktrace(System.out);        } finally {            ops.close();        }	} catch (Exception e) {		e.printstacktrace();	}	}

总结

以上是内存溢出为你收集整理的postgresql数据库保存和下载二进制文件的几种方式全部内容，希望文章能够帮你解决postgresql数据库保存和下载二进制文件的几种方式所遇到的程序开发问题。

如果觉得内存溢出网站内容还不错，欢迎将内存溢出网站推荐给程序员好友。