精致小巧的java相册制作方法
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2024-03-12 13:14:14
本文实例为大家分享了java相册制作方法，供大家参考，具体内容如下
注：
1)html上的图片是静态指定的。当更新了新的图片时必须手工更新...
本文实例为大家分享了java相册制作方法，供大家参考，具体内容如下
注：
1)html上的图片是静态指定的。当更新了新的图片时必须手工更新。所以使用servlet读取本地images中的所有图片，动态显示给用户。
2)如果存在中文名的图片，由于get方式无法直接传递中文，会导致出错。
主页面–index.jsp
<%@ page language="java" import="java.util.*" pageencoding="utf-8"%> <!doctype html public "-//w3c//dtd html 4.01 transitional//en"> <html> <head> <title>小小相册</title> </head> <body> <!-- http://localhost:8080/photosweb/ --> <h2>小小相册</h2> <a href="jsps/upload.jsp">上传相片</a> <a href="<%=request.getcontextpath() %>/servlet/showallimg">浏览相片</a> </body> </html>
页面显示:
上传图片功能:
<%@ page language="java" import="java.util.*" pageencoding="utf-8"%>
<!doctype html public "-//w3c//dtd html 4.01 transitional//en">
<html>
<head>
<title>小小相册</title>
</head>
<body>
<h2>小小相册</h2>
<form action="<%=request.getcontextpath() %>/servlet/uploadservlet" method="post" enctype="multipart/form-data">
照片:<input type="file" name="file"/><br/>
说明:<input type="text" name="desc"/><br/>
<input type="submit" value="上传"/>
</form>
</body>
</html>
package cn.hncu.servlet;
import java.io.file;
import java.io.ioexception;
import java.io.inputstream;
import java.io.printwriter;
import java.util.list;
import javax.servlet.requestdispatcher;
import javax.servlet.servletexception;
import javax.servlet.http.httpservlet;
import javax.servlet.http.httpservletrequest;
import javax.servlet.http.httpservletresponse;
import org.apache.commons.fileupload.fileitem;
import org.apache.commons.fileupload.fileuploadexception;
import org.apache.commons.fileupload.disk.diskfileitemfactory;
import org.apache.commons.fileupload.servlet.servletfileupload;
import org.apache.commons.io.fileutils;
import cn.hncu.dao.photodaoimpl;
import cn.hncu.domain.photomodel;
import cn.hncu.utils.myutils;
public class uploadservlet extends httpservlet {
public void doget(httpservletrequest request, httpservletresponse response)
throws servletexception, ioexception {
response.setcontenttype("text/html");
printwriter out = response.getwriter();
out.println("<!doctype html public \"-//w3c//dtd html 4.01 transitional//en\">");
out.println("<html>");
out.println(" <head><title>a servlet</title></head>");
out.println(" <body>");
out.print("错误信息:提交方式错误...不支持get方式上传照片");
out.println(" </body>");
out.println("</html>");
out.flush();
out.close();
}
public void dopost(httpservletrequest request, httpservletresponse response)
throws servletexception, ioexception {
request.setcharacterencoding("utf-8");
response.setcontenttype("text/html;charset=utf-8");
printwriter out = response.getwriter();
out.println("<!doctype html public \"-//w3c//dtd html 4.01 transitional//en\">");
out.println("<html>");
out.println(" <head><title>上传照片页面</title></head>");
out.println(" <body>");
//从上传表单提取信息:一,封装成photo值对象,调用dao层存储到后台
// 二,把上传的照片存储到服务器硬盘
//数据库:存储照片的存储情况的信息,,,真正的文件存储到硬盘
diskfileitemfactory dfi=new diskfileitemfactory();
file file=new file("d:/a");
if(file.exists()){
file.mkdirs();
}
dfi.setrepository(file);
servletfileupload upload=new servletfileupload(dfi);
upload.setsizemax(1024*1024*8);
upload.setheaderencoding("utf-8");//==>request.setcharacterencoding("utf-8");
try {
list<fileitem> list=upload.parserequest(request);
photomodel pm=new photomodel();
inputstream in=null;
for(fileitem fi:list){
if(fi.isformfield()){//这个不会有临时文件
string desc=fi.getstring("utf-8");
pm.setdesc(desc);
}else{
in=fi.getinputstream();
// string filename=fi.getfieldname();
// system.out.println("getfieldname:"+filename);
string filename=fi.getname();
// system.out.println("getname:"+filename);//测试:c:\users\adl1\pictures\saved pictures\111.jpg?
//卫条件
if(filename==null||filename.trim().equals("")){
out.println("没有选择文件,,,请必须选择一个文件...<br/>");
string strpath2=request.getcontextpath()+"/jsps/upload.jsp";
out.println("<a href=\""+strpath2+"\">返回上传页面</a>");
return;
}
pm.setdt(myutils.getcurrentdataime());
string realname=filename.substring(filename.lastindexof("\\"));//"\112.jpg"
system.out.println(realname.substring(1, realname.length()));
pm.setrealname(realname.substring(1, realname.length()));//把realname的"\"去掉
//ext扩展名
string ext=filename.substring(filename.lastindexof("."));
pm.setext(ext);
string id=myutils.getuuid();
pm.setid(id);
pm.setip(request.getremoteaddr());
pm.setdir(myutils.getdir(id));
}
}
//完成photo值对象的封装,调用dao进行存储
boolean boo=new photodaoimpl().sava(pm);
if(boo){
//完成数据库的存储,接下来是服务器硬盘的存储
//把照片存储到项目根目录下的photos文件夹中存储(以打散方式存储)
string path="photos/"+pm.getdir();
// system.out.println("path:"+path);//测试:photos/9/0
string filepath=getservletcontext().getrealpath(path);
// system.out.println("filepath:"+filepath);//测试:d:\apache-tomcat-7.0.30\webapps\photosweb\photos\9\0
file dir=new file(filepath);
if(!dir.exists()){
dir.mkdirs();
}
fileutils.copyinputstreamtofile(in, new file(filepath+"/"+pm.getid()+pm.getext()));
// //如果硬盘保存成功就跳转到主页面--转发
//// requestdispatcher rd=request.getrequestdispatcher(getservletcontext().getcontextpath()+"/index.jsp");//"/photosweb/photosweb/index.jsp"
// requestdispatcher rd=request.getrequestdispatcher("/index.jsp");//"/photosweb/index.jsp"g
// //java代码块和web.xml中url的开始"/"代表项目根目录
// rd.forward(request, response);
//这里不能使用转发,具体重定向和转发区别:http://blog.csdn.net/xanlv/article/details/52701085
//重定向
response.sendredirect(getservletcontext().getcontextpath()+"/index.jsp");
}else{
//数据库保存失败--留在上传页面
requestdispatcher rd=request.getrequestdispatcher("/jsps/upload..jsp");//"/photosweb/index.jsp"
rd.forward(request, response);
}
} catch (fileuploadexception e) {
throw new runtimeexception("上传失败", e);
}finally{//清临时文件
file f=new file("d:/a");
file fs[]=f.listfiles();
for(file ff:fs){
ff.delete();
}
}
out.println(" </body>");
out.println("</html>");
out.flush();
out.close();
}
}
页面显示效果:
浏览图片功能:
package cn.hncu.servlet;
import java.io.ioexception;
import java.io.printwriter;
import java.util.list;
import javax.servlet.servletexception;
import javax.servlet.http.httpservlet;
import javax.servlet.http.httpservletrequest;
import javax.servlet.http.httpservletresponse;
import cn.hncu.dao.photodaoimpl;
import cn.hncu.domain.photomodel;
public class showallimgservlet extends httpservlet {
public void doget(httpservletrequest request, httpservletresponse response)
throws servletexception, ioexception {
response.setcontenttype("text/html;charset=utf-8");
printwriter out = response.getwriter();
out.println("<!doctype html public \"-//w3c//dtd html 4.01 transitional//en\">");
out.println("<html>");
out.println(" <head><title>相册浏览</title></head>");
out.println(" <body>");
string strpath=request.getcontextpath()+"/jsps/upload.jsp";
out.println("<a href=\""+strpath+"\">返回上传页面</a>");
//string table="<table border='1px' width='100%' cellspacing='0' align='center'>"+//这种方式不可以设置水平居中
string table="<table border='1px' width='100%' cellspacing='0' style='text-align: center;'>"+
"<tr><th>文件名</th><th>上传日期时间</th><th>相片</th><th>相片说明</th><th>操作</th></tr>";
out.println(table);
//从dao层把所有的照片信息读取出来发送到前端页面
list<photomodel> list=new photodaoimpl().getallphotos();
for(photomodel pm:list){
out.println("<tr>");
out.println("<td width=80>"+pm.getrealname());
out.println("</td>");
out.println("<td width=120>"+pm.getdt());
out.println("</td>");
string path=request.getcontextpath()+"/photos/"+pm.getdir()+"/"+pm.getid()+pm.getext();
//system.out.println(path);//"/photosweb/photos/d/7/e78e18352b42410f85dbd8df834bd718.jpg"
//点击图片可以查看大图
out.println("<td width=100><a href='"+path+"'><img width=100 height=100 src='"+path+"'/></a>");
out.println("</td>");
out.println("<td width=200>"+pm.getdesc());
out.println("</td>");
out.println("<td width=80><a href='"+getservletcontext().getcontextpath()+"/servlet/delphoto?id="+pm.getid()+"'>删除图片</a>");
//out.println("<a href='<%=request.getcontextpath()%>/servlet/down?id="+pm.getid()+"'>下载图片</a></td>");
out.println("<br/><a href='"+getservletcontext().getcontextpath()+"/servlet/down?id="+pm.getid()+"'>下载图片</a></td>");
out.println("</tr>");
}
out.println("</table>");
out.println(" </body>");
out.println("</html>");
out.flush();
out.close();
}
public void dopost(httpservletrequest request, httpservletresponse response)
throws servletexception, ioexception {
response.setcontenttype("text/html;charset=utf-8");
printwriter out = response.getwriter();
out.println("<!doctype html public \"-//w3c//dtd html 4.01 transitional//en\">");
out.println("<html>");
out.println(" <head><title>a servlet</title></head>");
out.println(" <body>");
out.print("不支持post方式。。。");
out.println(" </body>");
out.println("</html>");
out.flush();
out.close();
}
}
页面显示效果:
删除功能:
package cn.hncu.servlet;
import java.io.file;
import java.io.ioexception;
import java.io.printwriter;
import javax.servlet.servletexception;
import javax.servlet.http.httpservlet;
import javax.servlet.http.httpservletrequest;
import javax.servlet.http.httpservletresponse;
import cn.hncu.dao.photodaoimpl;
import cn.hncu.domain.photomodel;
public class delphotoservlet extends httpservlet {
public void doget(httpservletrequest request, httpservletresponse response)
throws servletexception, ioexception {
response.setcontenttype("text/html;charset=utf-8");
printwriter out = response.getwriter();
out.println("<!doctype html public \"-//w3c//dtd html 4.01 transitional//en\">");
out.println("<html>");
out.println(" <head><title>删除照片页面</title></head>");
out.println(" <body>");
string id=request.getparameter("id");
string ip=request.getremoteaddr();
photodaoimpl dao=new photodaoimpl();
photomodel pm=dao.getsinglebyid(id);
if(pm!=null){
if(!pm.getip().equals(ip)){
out.println("您没有该图片的权限去删除...");
string strpath=request.getcontextpath()+"/servlet/showallimg";
out.println("<br/><a href=\""+strpath+"\">返回继续浏览</a>");
return ;
}
//删除包含两部分工作：清除数据库中的信息 和 删除服务器硬盘中的图片文件
//1清除数据库中的信息
boolean boo = dao.del(id);
//2删除服务器硬盘中的图片文件
if(boo){
string path="photos/"+pm.getdir()+"/"+pm.getid()+pm.getext();
string filepath=getservletcontext().getrealpath(path);
file f=new file(filepath);
if(f.exists()){
f.delete();
}
string strpath=request.getcontextpath()+"/servlet/showallimg";
// system.out.println(strpath);///photosweb/servlet/showphotos
out.println("删除成功...<br/><a href=\""+strpath+"\">返回浏览</a>");
}else{
out.println("删除数据库信息失败");
}
}else{
out.println("文件不存在...");
string strpath=request.getcontextpath()+"/servlet/showallimg";
out.println("<br/><a href=\""+strpath+"\">返回继续浏览</a>");
}
out.println(" </body>");
out.println("</html>");
out.flush();
out.close();
}
public void dopost(httpservletrequest request, httpservletresponse response)
throws servletexception, ioexception {
response.setcontenttype("text/html");
printwriter out = response.getwriter();
out.println("<!doctype html public \"-//w3c//dtd html 4.01 transitional//en\">");
out.println("<html>");
out.println(" <head><title>删除照片页面</title></head>");
out.println(" <body>");
out.print("不支持post方式...");
out.println(" </body>");
out.println("</html>");
out.flush();
out.close();
}
}
页面显示:
下载功能:
1.在html页面上使用超连接指向要下载的文件（不安全容易被盗链）。
问题：
如何确定本地资源？
servletcontext – 代表一个web项目。一个web项目只有一个servletcontext对像。
getrealpath(“/”); //d:/prm/tom/web/
需求分析：
在实际的开发中，下载哪一个文件，都是由用户动态选择的。
如，在我们项目images目录下，存在着很多图片文件。用户在页面上显示所有图片，用户可以点下载连接下载喜欢的图片。
详细设计：
使用静态网页显示所有图片。给每一个图片一个下以下载的超连接。
在超连接后面传递要下载的图片id。
在serivice中动态接收图片名。完成下载 。
package cn.hncu.servlet;
import java.io.file;
import java.io.fileinputstream;
import java.io.ioexception;
import java.io.inputstream;
import java.io.outputstream;
import java.io.printwriter;
import java.net.urlencoder;
import javax.servlet.requestdispatcher;
import javax.servlet.servletexception;
import javax.servlet.http.httpservlet;
import javax.servlet.http.httpservletrequest;
import javax.servlet.http.httpservletresponse;
import org.apache.commons.io.fileutils;
import cn.hncu.dao.photodaoimpl;
import cn.hncu.domain.photomodel;
public class downservlet extends httpservlet {
public void doget(httpservletrequest request, httpservletresponse response)
throws servletexception, ioexception {
//获取被下载图片的信息
tring id=request.getparameter("id");
photomodel pm=new photodaoimpl().getsinglebyid(id);
if(pm==null){
response.setcontenttype("text/html;charset=utf-8");
printwriter out = response.getwriter();
out.println("<!doctype html public \"-//w3c//dtd html 4.01 transitional//en\">");
out.println("<html>");
out.println(" <head><title>a servlet</title></head>");
out.println(" <body>");
response.getwriter().println("alert('该文本已不存在...')");
out.println(" </body>");
out.println("</html>");
out.flush();
out.close();
//getservletcontext().getcontextpath()
requestdispatcher rd=request.getrequestdispatcher("/servlet/down");//"/photosweb/index.jsp"
//java代码块和web.xml中url的开始"/"代表项目根目录
rd.forward(request, response);
}else{
//真正下载: 把服务器硬盘的照片文件读取出来发送给客户端(设置响应头)
//获取真实的文件
string realname=pm.getrealname();
realname=urlencoder.encode(realname, "utf-8");//如果是中文名必须转码，防止文件名中文乱码
// inputstream in=downservlet.class.getclassloader().getresourceasstream(realname);
//设置显示类型为下载
response.setcontenttype("application/force-download");
//设置响应头
response.setheader("content-disposition", "attachment;filename=\""+realname+"\"");
// string path=request.getcontextpath()+"/photos/"+pm.getdir()+"/"+pm.getid()+pm.getext();
string path="photos/"+pm.getdir()+"/"+pm.getid()+pm.getext();
string filepath=getservletcontext().getrealpath(path);
fileutils.copyinputstreamtofile(request.getinputstream(), new file(filepath));
inputstream in=new fileinputstream(filepath);
outputstream o=response.getoutputstream();
byte b[]=new byte[1024];
int len=0;
while((len=in.read(b))!=-1){
o.write(b, 0, len);
}
o.close();
}
}
public void dopost(httpservletrequest request, httpservletresponse response)
throws servletexception, ioexception {
response.setcontenttype("text/html");
printwriter out = response.getwriter();
out.println("<!doctype html public \"-//w3c//dtd html 4.01 transitional//en\">");
out.println("<html>");
out.println(" <head><title>a servlet</title></head>");
out.println(" <body>");
out.print(" 不支持");
out.println(" </body>");
out.println("</html>");
out.flush();
out.close();
}
}
页面显示效果:
配置文件web.xml
<?xml version="1.0" encoding="utf-8"?> <web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/xmlschema-instance" xsi:schemalocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"> <display-name></display-name> <servlet> <servlet-name>uploadservlet</servlet-name> <servlet-class>cn.hncu.servlet.uploadservlet</servlet-class> </servlet> <servlet> <servlet-name>showallimgservlet</servlet-name> <servlet-class>cn.hncu.servlet.showallimgservlet</servlet-class> </servlet> <servlet> <servlet-name>downservlet</servlet-name> <servlet-class>cn.hncu.servlet.downservlet</servlet-class> </servlet> <servlet> <servlet-name>delphotoservlet</servlet-name> <servlet-class>cn.hncu.servlet.delphotoservlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>uploadservlet</servlet-name> <url-pattern>/servlet/uploadservlet</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>showallimgservlet</servlet-name> <url-pattern>/servlet/showallimg</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>downservlet</servlet-name> <url-pattern>/servlet/down</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>delphotoservlet</servlet-name> <url-pattern>/servlet/delphoto</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> </web-app>
数据库:photos.xml
<?xml version="1.0" encoding="utf-8"?>
<photos>
<!-- 数据库设计
<photo id="uuid" realname="真实文件名.jpg"
dt="2016-10-03 19:51:31" ext=".jpg" dir="a/5"
ip="192.168.12.12">
<desc>照片说明信息</desc>
</photo>
-->
</photos>
值对象:photomodel.java
package cn.hncu.domain;
public class photomodel {
//photo值对象
private string id;//uuid
private string realname;//照片真实文件名
private string ext;//扩展名
private string dir;//文件打撒后存储的目录
private string dt;//上传日期时间
private string ip;//上传客户端的ip地址
private string desc;//照片说明
public string getid() {
return id;
}
public void setid(string id) {
this.id = id;
}
public string getrealname() {
return realname;
}
public void setrealname(string realname) {
this.realname = realname;
}
public string getext() {
return ext;
}
public void setext(string ext) {
this.ext = ext;
}
public string getdir() {
return dir;
}
public void setdir(string dir) {
this.dir = dir;
}
public string getdt() {
return dt;
}
public void setdt(string dt) {
this.dt = dt;
}
public string getip() {
return ip;
}
public void setip(string ip) {
this.ip = ip;
}
public string dreturn desc;
}
public void setdesc(string desc) {
this.desc = desc;
}
}
dao层:这里简写了,只写了实现类photodaoimpl.java
package cn.hncu.dao;
import java.util.arraylist;
import java.util.iterator;
import java.util.list;
import org.dom4j.document;
import org.dom4j.element;
import cn.hncu.domain.photomodel;
import cn.hncu.utils.domfactory;
public class photodaoimpl {
public boolean sava(photomodel pm){
document dom=domfactory.getdom();
element root=dom.getrootelement();
element e=root.addelement("photo");
e.addattribute("id", pm.getid());
e.addattribute("dir", pm.getdir());
e.addattribute("dt", pm.getdt());
e.addattribute("ext", pm.getext());
e.addattribute("ip", pm.getip());
e.addattribute("realname", pm.getrealname());
e.addelement("desc").settext(pm.getdesc());
boolean b=domfactory.save();
if(b){
return true;
}
return false;
}
public list<photomodel> getallphotos(){
list<photomodel> li=new arraylist<photomodel>();
document dom=domfactory.getdom();
element e=dom.getrootelement();
iterator<element> it=e.elementiterator();
while(it.hasnext()){
element ie=it.next();
photomodel pm=new photomodel();
pm.setid(ie.attributevalue("id"));
pm.setdir(ie.attributevalue("dir"));
pm.setdt(ie.attributevalue("dt"));
pm.setext(ie.attributevalue("ext"));
pm.setip(ie.attributevalue("ip"));
pm.setrealname(ie.attributevalue("realname"));
pm.setdesc(ie.elementtext("desc"));
li.add(pm);
}
return li;
}
public photomodel getsinglebyid(string id){
list<photomodel> li=getallphotos();
photomodel pm=new photomodel();
for(photomodel p:li){
if(p.getid().equals(id)){
return p;
}
}
return null;
}
public boolean del(string id) {
document dom=domfactory.getdom();
element e=(element) dom.selectsinglenode("//photo[@id='"+id+"']");
return e.getparent().remove(e);
}
}
工具类:
1.
package cn.hncu.utils;
import java.text.simpledateformat;
import java.util.date;
import java.util.uuid;
public class myutils {
private myutils() {
}
public static string getuuid(){
return uuid.randomuuid().tostring().replace("-", "");
}
private static simpledateformat sdf=new simpledateformat("yy-mm-dd hh:mm:ss");
public static string getcurrentdataime(){
return sdf.format(new date());
}
public static string getdir(string uuid){
string dir1=integer.tohexstring(uuid.hashcode()&0xf);
string dir2=integer.tohexstring((uuid.hashcode()&0xf0)>>4);
return dir1+"/"+dir2;
}
}
2.
package cn.hncu.utils;
import java.io.fileoutputstream;
import org.dom4j.document;
import org.dom4j.documentexception;
import org.dom4j.io.saxreader;
import org.dom4j.io.xmlwriter;
public class domfactory {
private static document dom;
private static string filename;
static{
try {
saxreader r=new saxreader();
//获取src下的资源文件
filename=domfactory.class.getclassloader().getresource("photos.xml").getpath();
system.out.println("users.xml的路径:"+filename);//"/d:/apache-tomcat-7.0.30/webapps/photosweb/web-inf/classes/photos.xml"
//注意:获取tomcat中当前项目classpath下的资源方式
dom=r.read(filename);
} catch (documentexception e) {
e.printstacktrace();
}
}
public static document getdom(){
return dom;
}
public static boolean save(){
xmlwriter w;
try {
w = new xmlwriter(new fileoutputstream(filename));
w.write(dom);
w.close();
return true;
} catch (exception e) {
return false;
}
}
}
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