java操作Redis
Java访问redis
Java操作redis
string（字符串）
hash（哈希）
list（列表）
set（集合）
zset(sorted set：有序集合)
package com.cjh; import redis.clients.jedis.Jedis; /** * @author * @site * @company * @create 2019-09-18 11:21 * * 讲的是java代码操作redis * 链接redis * 操作字符串 * 操作哈希 * 操作列表list * */ public class Dome1 { public static void main(String[] args) { Jedis jedis = new Jedis("192.168.198.129" ,6379); jedis.auth("123456"); System.out.println(jedis.ping()); //操作字符串 // jedis.set("aaa","zs"); // System.out.println(jedis.get("aaa")); // //操作哈希 // jedis.hset("user","uname","蔡徐坤"); // // jedis.hset("user","sex","女"); // //取一个对象 // System.out.println(jedis.hgetAll("user")); // //取一个对象里面的一个值 // System.out.println(jedis.hget("user", "uname")); //操作列表 jedis.lpush("hobby","唱","跳","rap"); System.out.println(jedis.lpop("hobby")); System.out.println(jedis.lpop("hobby")); System.out.println(jedis.rpop("hobby")); } }
package com.cjh; import redis.clients.jedis.Jedis; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.util.Map; /** * @author * @site * @company * @create 2019-09-18 11:46 */ @WebServlet("/getData") public class DomeServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { doPost(req,resp); } @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { //首页第一次是读数据库，后面是读缓存（在没有增删改的情况下） Jedis jedis = new Jedis("192.168.198.129" ,6379); jedis.auth("123456"); //从缓存里面获取用户信息 Map<String,String> currentUser= jedis.hgetAll("currentUser"); if(currentUser != null && currentUser.size()>0){ req.setAttribute("msg","从缓存里面拿数据"); req.setAttribute("currentUser",currentUser); } else{ //第一次登陆访问的是数据库 req.setAttribute("msg","从数据库里面拿数据"); String uname = "蔡徐坤"; String upwd = "123456"; //把数据中对应对象存储到缓存中 jedis.hset("currentUser","uanem","蔡徐坤"); jedis.hset("currentUser","upwd","123456"); //能获取到值是上面已经把数据存储到缓存中 currentUser= jedis.hgetAll("currentUser"); req.setAttribute("currentUser",currentUser); } req.getRequestDispatcher("/home.jsp").forward(req,resp); } }
项目运用Redis
优化luncec和网页静态化代码：
pom依赖：
<dependency>
<groupId>redis.clients</groupId>
<artifactId>jedis</artifactId>
<version>2.9.0</version>
</dependency>
只需要修改请求层里面的代码
package com.javaxl.blog.web; import java.io.File; import java.io.FileWriter; import java.io.IOException; import java.io.Writer; import java.nio.file.Paths; import java.sql.SQLException; import java.util.ArrayList; import java.util.Date; import java.util.HashMap; import java.util.List; import java.util.Map; import javax.servlet.http.HttpServletRequest; import org.apache.lucene.analysis.cn.smart.SmartChineseAnalyzer; import org.apache.lucene.document.Document; import org.apache.lucene.document.Field; import org.apache.lucene.document.StringField; import org.apache.lucene.document.TextField; import org.apache.lucene.index.DirectoryReader; import org.apache.lucene.index.IndexReader; import org.apache.lucene.index.IndexWriter; import org.apache.lucene.index.IndexWriterConfig; import org.apache.lucene.index.Term; import org.apache.lucene.queryparser.classic.QueryParser; import org.apache.lucene.search.IndexSearcher; import org.apache.lucene.search.Query; import org.apache.lucene.search.ScoreDoc; import org.apache.lucene.search.TopDocs; import org.apache.lucene.search.highlight.Formatter; import org.apache.lucene.search.highlight.Highlighter; import org.apache.lucene.search.highlight.QueryScorer; import org.apache.lucene.search.highlight.SimpleHTMLFormatter; import org.apache.lucene.store.Directory; import org.apache.lucene.store.FSDirectory; import org.apache.struts2.ServletActionContext; import com.alibaba.fastjson.JSON; import com.javaxl.blog.dao.BlogDao; import com.javaxl.blog.util.JsonUtils; import com.javaxl.blog.util.PropertiesUtil; import com.javaxl.blog.util.StringUtils; import freemarker.template.Configuration; import freemarker.template.Template; import freemarker.template.TemplateException; import redis.clients.jedis.Jedis; /** * 专门将网页静态化的类，这里不涉及到lucene * * @author Administrator * */ public class FreemarkerBlogAction { private String title; private String bid; private BlogDao blogDao = new BlogDao(); public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public String getBid() { return bid; } public void setBid(String bid) { this.bid = bid; } private static String add="192.168.198.129"; /** * 连接redis * @return */ public static Jedis Jedis() { Jedis jedis = new Jedis(add, 6379); jedis.auth("123456"); return jedis; } /** * 查询博客 * @return */ public String list() { try { HttpServletRequest request = ServletActionContext.getRequest(); Jedis jedis = Jedis(); if (StringUtils.isBlank(title)) { if(jedis.get("blogList")!=null && jedis.get("blogList").length()>0) { System.out.println("从缓存里面拿数据"); request.setAttribute("blogList", JSON.parse(jedis.get("blogList"))); } else { System.out.println("从数据里拿数据"); //从数据库里面拿数据 List<Map<String, Object>> list = this.blogDao.freemarker_list(title, null); //放人Redis缓存 jedis.set("blogList", JSON.toJSONString(list)); //传到jsp页面 request.setAttribute("blogList", list); } } else { SmartChineseAnalyzer analyzer = new SmartChineseAnalyzer(); IndexReader indexReader = DirectoryReader .open(FSDirectory.open(Paths.get(PropertiesUtil.getValue("indexPath")))); IndexSearcher searcher = new IndexSearcher(indexReader); // 拿一句话到索引目中的索引文件中的词库进行关键词碰撞 Query query = new QueryParser("title", analyzer).parse(title); TopDocs topDocs = searcher.search(query, 100); // 将碰撞出来的关键词给点亮 QueryScorer queryScorer = new QueryScorer(query); // 以什么形式点亮关键词 Formatter formatter = new SimpleHTMLFormatter("<span style='color:red;'><b>", "</span></b>"); Highlighter highlighter = new Highlighter(formatter, queryScorer); List<Map<String, Object>> blogList = new ArrayList<>(); Map<String, Object> map = null; ScoreDoc[] scoreDocs = topDocs.scoreDocs; for (ScoreDoc scoreDoc : scoreDocs) { map = new HashMap<>(); Document doc = searcher.doc(scoreDoc.doc); map.put("bid", doc.get("bid")); map.put("summary", doc.get("summary")); String titleHighlighter = doc.get("title"); if (StringUtils.isNotBlank(titleHighlighter)) { titleHighlighter = highlighter.getBestFragment(analyzer, "title", titleHighlighter); } map.put("title", titleHighlighter); blogList.add(map); } indexReader.close(); request.setAttribute("blogList", blogList); } } catch (Exception e) { // TODO: handle exception } return "blogList"; } public String show() { HttpServletRequest request = ServletActionContext.getRequest(); try { Map<String, Object> blog = this.blogDao.freemarker_show(bid).get(0); request.setAttribute("blog", blog); } catch (InstantiationException | IllegalAccessException | SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return "blogDetail"; } /** * 刷新全局索引 * * @return */ public String Starter() { IndexWriterConfig conf = new IndexWriterConfig(new SmartChineseAnalyzer()); Directory d; IndexWriter indexWriter = null; try { // 将原先的索引文件刪除 del(new File(PropertiesUtil.getValue("indexPath"))); d = FSDirectory.open(Paths.get(PropertiesUtil.getValue("indexPath"))); indexWriter = new IndexWriter(d, conf); // 为数据库中的所有数据构建索引 List<Map<String, Object>> list = blogDao.freemarker_list(null, null); for (Map<String, Object> map : list) { Document doc = new Document(); doc.add(new StringField("id", String.valueOf(map.get("bid")), Field.Store.YES)); doc.add(new StringField("bid", String.valueOf(map.get("bid")), Field.Store.YES)); doc.add(new TextField("title", (String) map.get("title"), Field.Store.YES)); doc.add(new TextField("summary", (String) map.get("summary"), Field.Store.YES)); indexWriter.addDocument(doc); } } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } finally { try { if (indexWriter != null) { indexWriter.close(); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } return "blogList"; } /** * 将原先的索引文件刪除 * * @param file */ private void del(File file) { // TODO Auto-generated method stub if (file.isDirectory()) { String[] children = file.list();// 获取文件夹下所有子文件夹 // 递归删除目录中的子目录下 for (int i = 0; i < children.length; i++) { del(new File(file, children[i])); } } // 目录空了，进行删除 file.delete(); } /** * 添加博客 * * @return */ public String add() { HttpServletRequest request = ServletActionContext.getRequest(); Map parameterMap = request.getParameterMap(); try { this.blogDao.add(parameterMap); //删除缓存 Jedis jedis = Jedis(); jedis.del("blogList"); // 获取当前博客的id int maxId = this.blogDao.maxId(); // 添加到lucene 索引库中 addIndex(maxId + "", parameterMap); // 进行网页静态化 addStaticPage(maxId + "", parameterMap); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } return "blogList"; } /** * 删除博客 * @return */ public String del() { try { // 数据库中删除博客 this.blogDao.del(bid); //删除缓存 Jedis jedis = Jedis(); jedis.del("blogList"); // 删除lucene中对应的文档 IndexWriter indexWriter = getIndexWriter(); indexWriter.deleteDocuments(new Term("id", bid)); indexWriter.forceMergeDeletes(); indexWriter.commit(); indexWriter.close(); // 删除页面 new File("E:\\y2\\17、freemarker\\javaxl_lunece_freemarker\\src\\main\\webapp\\freemarker\\" + bid + ".html").delete(); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } return "blogList"; } /** * 修改前 * @return */ public String perEidt() { HttpServletRequest request = ServletActionContext.getRequest(); try { Map<String, Object> map = this.blogDao.getBlogById(bid); request.setAttribute("map", map); } catch (InstantiationException | IllegalAccessException | SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return "edit"; } /** * 修改 * @return */ public String edit() { HttpServletRequest request = ServletActionContext.getRequest(); Map parameterMap = request.getParameterMap(); try { // 修改数据库中的值 this.blogDao.edit(request.getParameterMap()); //删除缓存 Jedis jedis = Jedis(); jedis.del("blogList"); // 修改lucene中的文档值 IndexWriter writer = getIndexWriter(); Document doc = new Document(); doc.add(new StringField("id", JsonUtils.getParamVal(parameterMap, "bid"), Field.Store.YES)); doc.add(new StringField("bid", JsonUtils.getParamVal(parameterMap, "bid"), Field.Store.YES)); doc.add(new TextField("title", JsonUtils.getParamVal(parameterMap, "title"), Field.Store.YES)); doc.add(new TextField("summary", JsonUtils.getParamVal(parameterMap, "summary"), Field.Store.YES)); writer.updateDocument(new Term("id", JsonUtils.getParamVal(parameterMap, "bid")), doc); writer.close(); // 修改静态页(相同id会之间覆盖) addStaticPage(JsonUtils.getParamVal(parameterMap, "bid"), parameterMap); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } return "blogList"; } /** * 将这篇博客进行网页静态化 * * @param string * @param parameterMap * @throws IOException */ private void addStaticPage(String id, Map parameterMap) throws IOException { // TODO Auto-generated method stub IndexWriter indexWriter = getIndexWriter(); Document doc = new Document(); doc.add(new StringField("id", id, Field.Store.YES)); doc.add(new StringField("bid", id, Field.Store.YES)); doc.add(new TextField("title", JsonUtils.getParamVal(parameterMap, "title"), Field.Store.YES)); doc.add(new TextField("summary", JsonUtils.getParamVal(parameterMap, "summary"), Field.Store.YES)); indexWriter.addDocument(doc); indexWriter.close(); } private IndexWriter getIndexWriter() throws IOException { // TODO Auto-generated method stub IndexWriterConfig conf = new IndexWriterConfig(new SmartChineseAnalyzer()); Directory d = FSDirectory.open(Paths.get(PropertiesUtil.getValue("indexPath"))); return new IndexWriter(d, conf); } /** * 添加到lucene 索引库中 * * @param string * @param parameterMap * @throws IOException * @throws TemplateException */ private void addIndex(String id, Map parameterMap) throws IOException, TemplateException { // TODO Auto-generated method stub // 1.创建配置类 Configuration configuration = new Configuration(Configuration.getVersion()); // 2.设置模板所在的目录 configuration.setDirectoryForTemplateLoading( new File("E:\\y2\\17、freemarker\\javaxl_lunece_freemarker\\src\\main\\webapp\\freemarker")); // 3.设置字符集 configuration.setDefaultEncoding("utf-8"); // 4.加载模板 (这是在 刚刚设置好的 目录下面去找) Template template = configuration.getTemplate("blogDetail.ftl"); Map map = new HashMap<>(); Map<String, Object> blog = new HashMap<>(); blog.put("bid", id); blog.put("title", JsonUtils.getParamVal(parameterMap, "title")); blog.put("releaseDate", new Date()); blog.put("btid", JsonUtils.getParamVal(parameterMap, "btid")); blog.put("clickHit", JsonUtils.getParamVal(parameterMap, "clickHit")); blog.put("content", JsonUtils.getParamVal(parameterMap, "content")); map.put("blog", blog); // // 6.创建Writer对象 Writer out = new FileWriter(new File( "E:\\y2\\17、freemarker\\javaxl_lunece_freemarker\\src\\main\\webapp\\freemarker\\" + id + ".html")); // 7.输出 template.process(map, out); // 8.关闭Writer对象 out.close(); } }
效果：
很明显从缓存里面拿数据要比从数据库里面拿数据要快
