JDK12安装教程及新特性浅谈

柔情只为你懂 2021-12-03 10:59 296阅读 0赞

# 一.安装教程 #

下载地址：[https://www.oracle.com/technetwork/java/javase/downloads/index.html][https_www.oracle.com_technetwork_java_javase_downloads_index.html]

### step 1 ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70][]

### step 2 ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 1][]

### step 3 ###

在山区网络不好......玩两把单机 回来继续安装

### step 4 ###

下载好的jdk，双击即可安装

![20190720095339616.png][]

建议更改安装位置

### ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 2][] ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 3][]

### step 5 ###

继续点击下一步安装，最后关闭即可

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 4][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 5][]

### step 6 ###

环境变量配置

右击【此电脑】，点击【属性】，选择【高级系统设置】

![20190720100630813.png][]

【高级】--> 【环境变量】

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 6][]

如果针对用户，可以 用户变量 配置，这里在系统变量配置全局

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 7][]

点击【新建】 配置 JAVA\_HOME 确定即可

# ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 8][] #

双击【Path】或单击【编辑】配置 Path

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 9][]

点击新增，输入 %JAVA\_HOME%\\bin，确定

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 10][]

***jdk9后不需要配置CLASSPATH变量***

### step 7  ###

验证jdk安装是否成功

打开【命令提示符】

方式1.

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 11][]

方式2. win+r

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 12][]

输入  java -version ，若出现java版本信息则说明安装成功，如下图：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjAzMjE5OQ_size_16_color_FFFFFF_t_70 13][]

# 二.新特性 #

地址：[http://openjdk.java.net/projects/][http_openjdk.java.net_projects]

### jdk12（GA 2019/03/19） ###

<table> 
 <tbody> 
  <tr> 
   <td>189:</td> 
   <td>Shenandoah: A Low-Pause-Time Garbage Collector (Experimental)</td> 
   <td>Shenandoah：低暂停时间垃圾收集器（实验性）</td> 
  </tr> 
  <tr> 
   <td>230:</td> 
   <td>Microbenchmark Suite</td> 
   <td>Microbenchmark套房</td> 
  </tr> 
  <tr> 
   <td>325:</td> 
   <td>Switch Expressions (Preview)</td> 
   <td>切换表达式（预览）</td> 
  </tr> 
  <tr> 
   <td>334:</td> 
   <td>JVM Constants API</td> 
   <td>JVM常量API</td> 
  </tr> 
  <tr> 
   <td>340:</td> 
   <td>One AArch64 Port, Not Two</td> 
   <td>一个AArch64端口，而不是两个</td> 
  </tr> 
  <tr> 
   <td>341:</td> 
   <td>Default CDS Archives</td> 
   <td>默认CDS档案</td> 
  </tr> 
  <tr> 
   <td>344:</td> 
   <td>Abortable Mixed Collections for G1</td> 
   <td>G1的可流动混合收集</td> 
  </tr> 
  <tr> 
   <td>346:</td> 
   <td>Promptly Return Unused Committed Memory from G1</td> 
   <td>从G1中立即返回未使用的已提交内存</td> 
  </tr> 
 </tbody> 
</table>

**a--**切换表达式，省去 break

switch (day) {
    case SATURDAY, SUNDAY -> log.info("去旅游");
    case TUESDAY -> log.info("上班");
    case THURSDAY -> log.info("上课");
    }
    
    
    String whereTo = switch (day) {
    case SATURDAY, SUNDAY -> "去旅游";
    case TUESDAY -> "上班";
    case THURSDAY -> "上课";
    };

### jdk11（GA 2018/09/25) ###

<table> 
 <tbody> 
  <tr> 
   <td>181:</td> 
   <td>Nest-Based Access Control</td> 
   <td>基于嵌套的访问控制</td> 
  </tr> 
  <tr> 
   <td>309:&nbsp;</td> 
   <td>Dynamic Class-File Constants</td> 
   <td>动态类 - 文件常量</td> 
  </tr> 
  <tr> 
   <td>315:&nbsp;</td> 
   <td>Improve Aarch64 Intrinsics</td> 
   <td>改进Aarch64内在函数</td> 
  </tr> 
  <tr> 
   <td>318:&nbsp;</td> 
   <td>Epsilon: A No-Op Garbage Collector</td> 
   <td>Epsilon：无操作垃圾收集器</td> 
  </tr> 
  <tr> 
   <td>320:&nbsp;</td> 
   <td>Remove the Java EE and CORBA Modules</td> 
   <td>移除Java EE和CORBA模块</td> 
  </tr> 
  <tr> 
   <td>321:&nbsp;</td> 
   <td>HTTP Client (Standard)</td> 
   <td>HTTP客户端（标准）</td> 
  </tr> 
  <tr> 
   <td>323:&nbsp;</td> 
   <td>Local-Variable Syntax for Lambda Parameters</td> 
   <td>本地变量Lambda参数</td> 
  </tr> 
  <tr> 
   <td>324:&nbsp;</td> 
   <td>Key Agreement with Curve25519 and Curve448</td> 
   <td>与Curve25519和Curve448的密钥协议</td> 
  </tr> 
  <tr> 
   <td>327:&nbsp;</td> 
   <td>Unicode 10</td> 
   <td>Unicode 10</td> 
  </tr> 
  <tr> 
   <td>328:&nbsp;</td> 
   <td>Flight Recorder</td> 
   <td> <p>Flight Recorder（飞行记录器），基于OS、JVM和JDK的事件</p> <p>产生的数据收集框架</p> </td> 
  </tr> 
  <tr> 
   <td>329:&nbsp;</td> 
   <td>ChaCha20 and Poly1305 Cryptographic Algorithms</td> 
   <td>ChaCha20和Poly1305加密算法</td> 
  </tr> 
  <tr> 
   <td>330:&nbsp;</td> 
   <td>Launch Single-File Source-Code Programs</td> 
   <td>启动单文件源代码程序</td> 
  </tr> 
  <tr> 
   <td>331:&nbsp;</td> 
   <td>Low-Overhead Heap Profiling</td> 
   <td>低开销堆分析</td> 
  </tr> 
  <tr> 
   <td>332:&nbsp;</td> 
   <td>Transport Layer Security (TLS) 1.3</td> 
   <td>传输层安全性（TLS）1.3</td> 
  </tr> 
  <tr> 
   <td>333:&nbsp;</td> 
   <td>ZGC: A Scalable Low-Latency Garbage Collector(Experimental)</td> 
   <td>ZGC：可扩展的低延迟垃圾收集器（实验性）</td> 
  </tr> 
  <tr> 
   <td>335:&nbsp;</td> 
   <td>Deprecate the Nashorn JavaScript Engine</td> 
   <td>弃用Nashorn JavaScript引擎</td> 
  </tr> 
  <tr> 
   <td>336:&nbsp;</td> 
   <td>Deprecate the Pack200 Tools and API</td> 
   <td>弃用Pack200工具和API</td> 
  </tr> 
 </tbody> 
</table>

**a--**字符串加强

// 复制
    
    "Java".repeat(3); // "JavaJavaJava"
    
    //统计 行数
    
    "A\nB\nC\nA\nB\nC".lines().count(); // 6

### jdk10（GA 2018/03/20） ###

<table> 
 <tbody> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/286" rel="nofollow">286:&nbsp;</a></td> 
   <td>Local-Variable Type Inference</td> 
   <td>局部变量类型推断</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/296" rel="nofollow">296:&nbsp;</a></td> 
   <td>Consolidate the JDK Forest into a Single Repository</td> 
   <td>将JDK林合并到单个存储库</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/304" rel="nofollow">304:&nbsp;</a></td> 
   <td>Garbage-Collector Interface</td> 
   <td>垃圾收集器接口</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/307" rel="nofollow">307:&nbsp;</a></td> 
   <td>Parallel Full GC for G1</td> 
   <td>G1的并行全GC</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/310" rel="nofollow">310:&nbsp;</a></td> 
   <td>Application Class-Data Sharing</td> 
   <td>应用程序类 - 数据共享</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/312" rel="nofollow">312:&nbsp;</a></td> 
   <td>Thread-Local Handshakes</td> 
   <td>线程局部握手</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/313" rel="nofollow">313:&nbsp;</a></td> 
   <td>Remove the Native-Header Generation Tool (javah)</td> 
   <td>移除本机头生成工具（javah）</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/314" rel="nofollow">314:&nbsp;</a></td> 
   <td>Additional Unicode Language-Tag Extensions</td> 
   <td>附加的Unicode语言 - 标记扩展</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/316" rel="nofollow">316:&nbsp;</a></td> 
   <td>Heap Allocation on Alternative Memory Devices</td> 
   <td>替代存储器设备上的堆分配</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/317" rel="nofollow">317:&nbsp;</a></td> 
   <td>Experimental Java-Based JIT Compiler</td> 
   <td>基于Java的实验JIT编译器</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/319" rel="nofollow">319:&nbsp;</a></td> 
   <td>Root Certificates</td> 
   <td>根证书</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/322" rel="nofollow">322:&nbsp;</a></td> 
   <td>Time-Based Release Versioning</td> 
   <td>基于时间的发布版本控制</td> 
  </tr> 
 </tbody> 
</table>

**    a--**使用局部类型----var关键词定义

var list = new LinkedList<String>();

## ##

### jdk9 ###

<table> 
 <tbody> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/102" rel="nofollow">102:&nbsp;</a></td> 
   <td>Process API Updates</td> 
   <td>处理API更新</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/110" rel="nofollow">110:&nbsp;</a></td> 
   <td>HTTP 2 Client</td> 
   <td>HTTP 2客户端</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/143" rel="nofollow">143:&nbsp;</a></td> 
   <td>Improve Contended Locking</td> 
   <td>改进竞争锁定</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/158" rel="nofollow">158:&nbsp;</a></td> 
   <td>Unified JVM Logging</td> 
   <td>统一JVM记录</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/165" rel="nofollow">165:&nbsp;</a></td> 
   <td>Compiler Control</td> 
   <td>编译器控制</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/193" rel="nofollow">193:&nbsp;</a></td> 
   <td>Variable Handles</td> 
   <td>可变句柄</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/197" rel="nofollow">197:&nbsp;</a></td> 
   <td>Segmented Code Cache</td> 
   <td>分段代码高速缓存</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/199" rel="nofollow">199:&nbsp;</a></td> 
   <td>Smart Java Compilation, Phase Two</td> 
   <td>智能Java编译，阶段二</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/200" rel="nofollow">200:&nbsp;</a></td> 
   <td>The Modular JDK</td> 
   <td>模块化JDK</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/201" rel="nofollow">201:&nbsp;</a></td> 
   <td>Modular Source Code</td> 
   <td>模块化源代码</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/211" rel="nofollow">211:&nbsp;</a></td> 
   <td>Elide Deprecation Warnings on Import Statements</td> 
   <td>导入语句的Elide&nbsp;弃用警告</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/212" rel="nofollow">212:&nbsp;</a></td> 
   <td>Resolve Lint and Doclint Warnings</td> 
   <td>解决Lint和Doclint警告</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/213" rel="nofollow">213:&nbsp;</a></td> 
   <td>Milling Project Coin</td> 
   <td>铣削项目硬币</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/214" rel="nofollow">214:&nbsp;</a></td> 
   <td>Remove GC Combinations Deprecated in JDK 8</td> 
   <td>删除GC组合JDK 8中不推荐使用</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/215" rel="nofollow">215:&nbsp;</a></td> 
   <td>Tiered Attribution for javac</td> 
   <td>javac的分层归因</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/216" rel="nofollow">216:&nbsp;</a></td> 
   <td>Process Import Statements Correctly</td> 
   <td>正确处理导入语句</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/217" rel="nofollow">217:&nbsp;</a></td> 
   <td>Annotations Pipeline 2.0</td> 
   <td>注释管道2.0</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/219" rel="nofollow">219:&nbsp;</a></td> 
   <td>Datagram Transport Layer Security (DTLS)</td> 
   <td>数据报传输层安全性（DTLS）</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/220" rel="nofollow">220:&nbsp;</a></td> 
   <td>Modular Run-Time Images</td> 
   <td>模块化运行时图像</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/221" rel="nofollow">221:&nbsp;</a></td> 
   <td>Simplified Doclet API</td> 
   <td>简化的Doclet API</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/222" rel="nofollow">222:&nbsp;</a></td> 
   <td>jshell: The Java Shell (Read-Eval-Print Loop)</td> 
   <td>jshell：Java Shell（读取 - 评估 - 打印循环）</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/223" rel="nofollow">223:&nbsp;</a></td> 
   <td>New Version-String Scheme</td> 
   <td>新的Version-String Scheme</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/224" rel="nofollow">224:&nbsp;</a></td> 
   <td>HTML5 Javadoc</td> 
   <td>HTML5 Javadoc</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/225" rel="nofollow">225:&nbsp;</a></td> 
   <td>Javadoc Search</td> 
   <td>Javadoc Search</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/226" rel="nofollow">226:&nbsp;</a></td> 
   <td>UTF-8 Property Files</td> 
   <td>UTF-8属性文件</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/227" rel="nofollow">227:&nbsp;</a></td> 
   <td>Unicode 7.0</td> 
   <td>Unicode 7.0</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/228" rel="nofollow">228:&nbsp;</a></td> 
   <td>Add More Diagnostic Commands</td> 
   <td>添加更多诊断命令</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/229" rel="nofollow">229:&nbsp;</a></td> 
   <td>Create PKCS12 Keystores by Default</td> 
   <td>默认创建PKCS12密钥库</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/231" rel="nofollow">231:&nbsp;</a></td> 
   <td>Remove Launch-Time JRE Version Selection</td> 
   <td>删除启动时JRE版本选择</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/232" rel="nofollow">232:&nbsp;</a></td> 
   <td>Improve Secure Application Performance</td> 
   <td>提高安全应用程序性能</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/233" rel="nofollow">233:&nbsp;</a></td> 
   <td>Generate Run-Time Compiler Tests Automatically</td> 
   <td>自动生成运行时编译器测试</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/235" rel="nofollow">235:&nbsp;</a></td> 
   <td>Test Class-File Attributes Generated by javac</td> 
   <td>测试类文件属性由javac生成</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/236" rel="nofollow">236:&nbsp;</a></td> 
   <td>Parser API for Nashorn</td> 
   <td>Nashorn的解析器API</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/237" rel="nofollow">237:&nbsp;</a></td> 
   <td>Linux/AArch64 Port</td> 
   <td>Linux / AArch64端口</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/238" rel="nofollow">238:&nbsp;</a></td> 
   <td>Multi-Release JAR Files</td> 
   <td>多版本JAR文件</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/240" rel="nofollow">240:&nbsp;</a></td> 
   <td>Remove the JVM TI hprof Agent</td> 
   <td>删除JVM TI hprof代理</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/241" rel="nofollow">241:&nbsp;</a></td> 
   <td>Remove the jhat Tool</td> 
   <td>删除jhat工具</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/243" rel="nofollow">243:&nbsp;</a></td> 
   <td>Java-Level JVM Compiler Interface</td> 
   <td>Java级JVM编译器接口</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/244" rel="nofollow">244:&nbsp;</a></td> 
   <td>TLS Application-Layer Protocol Negotiation Extension</td> 
   <td>TLS应用层协议协商扩展</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/245" rel="nofollow">245:&nbsp;</a></td> 
   <td>Validate JVM Command-Line Flag Arguments</td> 
   <td>验证JVM命令行标志参数</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/246" rel="nofollow">246:&nbsp;</a></td> 
   <td>Leverage CPU Instructions for GHASH and RSA</td> 
   <td>利用GHASH和RSA的CPU指令</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/247" rel="nofollow">247:&nbsp;</a></td> 
   <td>Compile for Older Platform Versions</td> 
   <td>编译较旧的平台版本</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/248" rel="nofollow">248:&nbsp;</a></td> 
   <td>Make G1 the Default Garbage Collector</td> 
   <td>使G1成为默认垃圾收集器</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/249" rel="nofollow">249:&nbsp;</a></td> 
   <td>OCSP Stapling for TLS</td> 
   <td>针对TLS的OCSP装订</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/250" rel="nofollow">250:&nbsp;</a></td> 
   <td>Store Interned Strings in CDS Archives</td> 
   <td>在CDS存档中存储间隔字符串</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/251" rel="nofollow">251:&nbsp;</a></td> 
   <td>Multi-Resolution Images</td> 
   <td>多分辨率图像</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/252" rel="nofollow">252:&nbsp;</a></td> 
   <td>Use CLDR Locale Data by Default</td> 
   <td>默认使用CLDR区域设置数据</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/253" rel="nofollow">253:&nbsp;</a></td> 
   <td>Prepare JavaFX UI Controls &amp; CSS APIs for Modularization</td> 
   <td>为模块化准备JavaFX UI控件和CSS API</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/254" rel="nofollow">254:&nbsp;</a></td> 
   <td>Compact Strings</td> 
   <td>紧凑字符串</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/255" rel="nofollow">255:&nbsp;</a></td> 
   <td>Merge Selected Xerces 2.11.0 Updates into JAXP</td> 
   <td>将选定的Xerces 2.11.0更新合并到JAXP</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/256" rel="nofollow">256:&nbsp;</a></td> 
   <td>BeanInfo Annotations</td> 
   <td>BeanInfo注释</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/257" rel="nofollow">257:&nbsp;</a></td> 
   <td>Update JavaFX/Media to Newer Version of GStreamer</td> 
   <td>将JavaFX / Media更新到更新版本的GStreamer</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/258" rel="nofollow">258:&nbsp;</a></td> 
   <td>HarfBuzz Font-Layout Engine</td> 
   <td>HarfBuzzFonts-Layout Engine</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/259" rel="nofollow">259:&nbsp;</a></td> 
   <td>Stack-Walking API</td> 
   <td>Stack-Walking API</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/260" rel="nofollow">260:&nbsp;</a></td> 
   <td>Encapsulate Most Internal APIs</td> 
   <td>封装大多数内部API</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/261" rel="nofollow">261:&nbsp;</a></td> 
   <td>Module System</td> 
   <td>模块系统</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/262" rel="nofollow">262:&nbsp;</a></td> 
   <td>TIFF Image I/O</td> 
   <td>TIFF图像I / O</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/263" rel="nofollow">263:&nbsp;</a></td> 
   <td>HiDPI Graphics on Windows and Linux</td> 
   <td>Windows和Linux上的HiDPI图形</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/264" rel="nofollow">264:&nbsp;</a></td> 
   <td>Platform Logging API and Service</td> 
   <td>平台记录API和服务</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/265" rel="nofollow">265:&nbsp;</a></td> 
   <td>Marlin Graphics Renderer</td> 
   <td>Marlin图形渲染器</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/266" rel="nofollow">266:&nbsp;</a></td> 
   <td>More Concurrency Updates</td> 
   <td>更多并发更新</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/267" rel="nofollow">267:&nbsp;</a></td> 
   <td>Unicode 8.0</td> 
   <td>Unicode 8.0</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/268" rel="nofollow">268:&nbsp;</a></td> 
   <td>XML Catalogs</td> 
   <td>XML目录</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/269" rel="nofollow">269:&nbsp;</a></td> 
   <td>Convenience Factory Methods for Collections</td> 
   <td>集合的便利工厂方法</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/270" rel="nofollow">270:&nbsp;</a></td> 
   <td>Reserved Stack Areas for Critical Sections</td> 
   <td>保留关键部分的堆栈区域</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/271" rel="nofollow">271:&nbsp;</a></td> 
   <td>Unified GC Logging</td> 
   <td>统一GC记录</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/272" rel="nofollow">272:&nbsp;</a></td> 
   <td>Platform-Specific Desktop Features</td> 
   <td>特定于平台的桌面功能</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/273" rel="nofollow">273:&nbsp;</a></td> 
   <td>DRBG-Based SecureRandom Implementations</td> 
   <td>基于DRBG的SecureRandom实现</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/274" rel="nofollow">274:&nbsp;</a></td> 
   <td>Enhanced Method Handles</td> 
   <td>增强的方法句柄</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/275" rel="nofollow">275:&nbsp;</a></td> 
   <td>Modular Java Application Packaging</td> 
   <td>模块化Java应用程序打包</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/276" rel="nofollow">276:&nbsp;</a></td> 
   <td>Dynamic Linking of Language-Defined Object Models</td> 
   <td>语言定义的对象模型的动态链接</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/277" rel="nofollow">277:&nbsp;</a></td> 
   <td>Enhanced Deprecation</td> 
   <td>增强的弃使</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/278" rel="nofollow">278:&nbsp;</a></td> 
   <td>Additional Tests for Humongous Objects in G1</td> 
   <td>G1中的对象中的附加测试</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/279" rel="nofollow">279:&nbsp;</a></td> 
   <td>Improve Test-Failure Troubleshooting</td> 
   <td>改进测试失败故障排除</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/280" rel="nofollow">280:&nbsp;</a></td> 
   <td>Indify String Concatenation</td> 
   <td>表示字符串连接</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/281" rel="nofollow">281:&nbsp;</a></td> 
   <td>HotSpot C++ Unit-Test Framework</td> 
   <td>HotSpot C ++单元测试框架</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/282" rel="nofollow">282:&nbsp;</a></td> 
   <td>jlink: The Java Linker</td> 
   <td>jlink：Java链接器</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/283" rel="nofollow">283:&nbsp;</a></td> 
   <td>Enable GTK 3 on Linux</td> 
   <td>在Linux上启用GTK 3</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/284" rel="nofollow">284:&nbsp;</a></td> 
   <td>New HotSpot Build System</td> 
   <td>新的HotSpot构建系统</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/285" rel="nofollow">285:&nbsp;</a></td> 
   <td>Spin-Wait Hints</td> 
   <td>旋转等待提示</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/287" rel="nofollow">287:&nbsp;</a></td> 
   <td>SHA-3 Hash Algorithms</td> 
   <td>SHA-3哈希算法</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/288" rel="nofollow">288:&nbsp;</a></td> 
   <td>Disable SHA-1 Certificates</td> 
   <td>禁用SHA-1证书</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/289" rel="nofollow">289:&nbsp;</a></td> 
   <td>Deprecate the Applet API</td> 
   <td>弃用Applet API</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/290" rel="nofollow">290:&nbsp;</a></td> 
   <td>Filter Incoming Serialization Data</td> 
   <td>过滤传入的序列化数据</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/291" rel="nofollow">291:&nbsp;</a></td> 
   <td>Deprecate the Concurrent Mark Sweep (CMS) Garbage Collector</td> 
   <td>弃用并发标记扫描（CMS）垃圾收集器</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/292" rel="nofollow">292:&nbsp;</a></td> 
   <td>Implement Selected ECMAScript 6 Features in Nashorn</td> 
   <td>在Nashorn中实现选定的ECMAScript 6功能</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/294" rel="nofollow">294:&nbsp;</a></td> 
   <td>Linux/s390x Port</td> 
   <td>Linux / s390x端口</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/295" rel="nofollow">295:&nbsp;</a></td> 
   <td>Ahead-of-Time Compilation</td> 
   <td>提前编译</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/297" rel="nofollow">297:&nbsp;</a></td> 
   <td>Unified arm32/arm64 Port</td> 
   <td>统一arm32 / arm64端口</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/298" rel="nofollow">298:&nbsp;</a></td> 
   <td>Remove Demos and Samples</td> 
   <td>删除演示和示例</td> 
  </tr> 
  <tr> 
   <td><a href="http://openjdk.java.net/jeps/299" rel="nofollow">299:&nbsp;</a></td> 
   <td>Reorganize Documentation</td> 
   <td>重新组织文档</td> 
  </tr> 
 </tbody> 
</table>

**a--**JShell:工具像脚本语言一样来运行，在控制台启动 jshell ，获取或校验某些表达式的值，省去main方法测试。

如：

![20190720203010196.png][]

**b--**允许接口定义私有方法，私有方法可以作为通用方法放在默认方法中调用。

[https_www.oracle.com_technetwork_java_javase_downloads_index.html]: https://www.oracle.com/technetwork/java/javase/downloads/index.html
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[http_openjdk.java.net_projects]: http://openjdk.java.net/projects/
[20190720203010196.png]: /images/20211203/46126d4968bf48ec912aec7679590414.png