flink源码分析 - jar包中提取主类和第三方依赖

flink版本: flink-1.11.2

提取主类代码位置: org.apache.flink.client.program.PackagedProgram#getEntryPointClassNameFromJar

提取第三方依赖代码位置:org.apache.flink.client.program.PackagedProgram#getJobJarAndDependencies

代码逻辑比较简单，此处不再赘述，在此记录方便后续使用

完整代码:

/** Licensed to the Apache Software Foundation (ASF) under one* or more contributor license agreements.  See the NOTICE file* distributed with this work for additional information* regarding copyright ownership.  The ASF licenses this file* to you under the Apache License, Version 2.0 (the* "License"); you may not use this file except in compliance* with the License.  You may obtain a copy of the License at**     http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and* limitations under the License.*/package org.apache.flink.client.program;import org.apache.flink.api.common.ProgramDescription;
import org.apache.flink.client.ClientUtils;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.runtime.jobgraph.SavepointRestoreSettings;
import org.apache.flink.util.InstantiationUtil;
import org.apache.flink.util.JarUtils;import javax.annotation.Nullable;import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.net.MalformedURLException;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Random;
import java.util.jar.Attributes;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.jar.Manifest;
import java.util.stream.Collectors;import static org.apache.flink.client.program.PackagedProgramUtils.isPython;
import static org.apache.flink.util.Preconditions.checkArgument;
import static org.apache.flink.util.Preconditions.checkNotNull;/*** This class encapsulates represents a program, packaged in a jar file. It supplies functionality* to extract nested libraries, search for the program entry point, and extract a program plan.*/
public class PackagedProgram {/*** Property name of the entry in JAR manifest file that describes the Flink specific entry* point.*/public static final String MANIFEST_ATTRIBUTE_ASSEMBLER_CLASS = "program-class";/*** Property name of the entry in JAR manifest file that describes the class with the main* method.*/public static final String MANIFEST_ATTRIBUTE_MAIN_CLASS = "Main-Class";// --------------------------------------------------------------------------------------------private final URL jarFile;private final String[] args;private final Class<?> mainClass;private final List<File> extractedTempLibraries;private final List<URL> classpaths;private final ClassLoader userCodeClassLoader;private final SavepointRestoreSettings savepointSettings;/*** Flag indicating whether the job is a Python job.*/private final boolean isPython;/*** Creates an instance that wraps the plan defined in the jar file using the given arguments.* For generating the plan the class defined in the className parameter is used.** @param jarFile             The jar file which contains the plan.* @param classpaths          Additional classpath URLs needed by the Program.* @param entryPointClassName Name of the class which generates the plan. Overrides the class*                            defined in the jar file manifest.* @param configuration       Flink configuration which affects the classloading policy of the Program*                            execution.* @param args                Optional. The arguments used to create the pact plan, depend on implementation of*                            the pact plan. See getDescription().* @throws ProgramInvocationException This invocation is thrown if the Program can't be properly*                                    loaded. Causes may be a missing / wrong class or manifest files.*/private PackagedProgram(@Nullable File jarFile, List<URL> classpaths,@Nullable String entryPointClassName, Configuration configuration,SavepointRestoreSettings savepointRestoreSettings, String... args)throws ProgramInvocationException {this.classpaths = checkNotNull(classpaths);this.savepointSettings = checkNotNull(savepointRestoreSettings);this.args = checkNotNull(args);checkArgument(jarFile != null || entryPointClassName != null,"Either the jarFile or the entryPointClassName needs to be non-null.");// whether the job is a Python job.this.isPython = isPython(entryPointClassName);// load the jar file if existsthis.jarFile = loadJarFile(jarFile);assert this.jarFile != null || entryPointClassName != null;// now that we have an entry point, we can extract the nested jar files (if any)this.extractedTempLibraries = this.jarFile == null ? Collections.emptyList(): extractContainedLibraries(this.jarFile);this.userCodeClassLoader = ClientUtils.buildUserCodeClassLoader(getJobJarAndDependencies(),classpaths, getClass().getClassLoader(), configuration);// load the entry point classthis.mainClass = loadMainClass(// if no entryPointClassName name was given, we try and look one up through// the manifestentryPointClassName != null ? entryPointClassName : getEntryPointClassNameFromJar(this.jarFile),userCodeClassLoader);if (!hasMainMethod(mainClass)) {throw new ProgramInvocationException("The given program class does not have a main(String[]) method.");}}public SavepointRestoreSettings getSavepointSettings() {return savepointSettings;}public String[] getArguments() {return this.args;}public String getMainClassName() {return this.mainClass.getName();}/*** Returns the description provided by the Program class. This may contain a description of the* plan itself and its arguments.** @return The description of the PactProgram's input parameters.* @throws ProgramInvocationException This invocation is thrown if the Program can't be properly*                                    loaded. Causes may be a missing / wrong class or manifest files.*/@Nullablepublic String getDescription() throws ProgramInvocationException {if (ProgramDescription.class.isAssignableFrom(this.mainClass)) {ProgramDescription descr;try {descr =InstantiationUtil.instantiate(this.mainClass.asSubclass(ProgramDescription.class),ProgramDescription.class);} catch (Throwable t) {return null;}try {return descr.getDescription();} catch (Throwable t) {throw new ProgramInvocationException("Error while getting the program description"+ (t.getMessage() == null ? "." : ": " + t.getMessage()),t);}} else {return null;}}/*** This method assumes that the context environment is prepared, or the execution will be a* local execution by default.*/public void invokeInteractiveModeForExecution() throws ProgramInvocationException {callMainMethod(mainClass, args);}/*** Returns the classpaths that are required by the program.** @return List of {@link java.net.URL}s.*/public List<URL> getClasspaths() {return this.classpaths;}/*** Gets the {@link java.lang.ClassLoader} that must be used to load user code classes.** @return The user code ClassLoader.*/public ClassLoader getUserCodeClassLoader() {return this.userCodeClassLoader;}/*** Returns all provided libraries needed to run the program.*/public List<URL> getJobJarAndDependencies() {List<URL> libs = new ArrayList<URL>(extractedTempLibraries.size() + 1);if (jarFile != null) {libs.add(jarFile);}for (File tmpLib : extractedTempLibraries) {try {libs.add(tmpLib.getAbsoluteFile().toURI().toURL());} catch (MalformedURLException e) {throw new RuntimeException("URL is invalid. This should not happen.", e);}}if (isPython) {libs.add(PackagedProgramUtils.getPythonJar());}return libs;}/*** Returns all provided libraries needed to run the program.*/public static List<URL> getJobJarAndDependencies(File jarFile, @Nullable String entryPointClassName) throws ProgramInvocationException {URL jarFileUrl = loadJarFile(jarFile);List<File> extractedTempLibraries =jarFileUrl == null? Collections.emptyList(): extractContainedLibraries(jarFileUrl);List<URL> libs = new ArrayList<URL>(extractedTempLibraries.size() + 1);if (jarFileUrl != null) {libs.add(jarFileUrl);}for (File tmpLib : extractedTempLibraries) {try {libs.add(tmpLib.getAbsoluteFile().toURI().toURL());} catch (MalformedURLException e) {throw new RuntimeException("URL is invalid. This should not happen.", e);}}if (isPython(entryPointClassName)) {libs.add(PackagedProgramUtils.getPythonJar());}return libs;}/*** Deletes all temporary files created for contained packaged libraries.*/public void deleteExtractedLibraries() {deleteExtractedLibraries(this.extractedTempLibraries);this.extractedTempLibraries.clear();}private static boolean hasMainMethod(Class<?> entryClass) {Method mainMethod;try {mainMethod = entryClass.getMethod("main", String[].class);} catch (NoSuchMethodException e) {return false;} catch (Throwable t) {throw new RuntimeException("Could not look up the main(String[]) method from the class "+ entryClass.getName()+ ": "+ t.getMessage(),t);}return Modifier.isStatic(mainMethod.getModifiers())&& Modifier.isPublic(mainMethod.getModifiers());}private static void callMainMethod(Class<?> entryClass, String[] args) throws ProgramInvocationException {Method mainMethod;if (!Modifier.isPublic(entryClass.getModifiers())) {throw new ProgramInvocationException("The class " + entryClass.getName() + " must be public.");}try {mainMethod = entryClass.getMethod("main", String[].class);} catch (NoSuchMethodException e) {throw new ProgramInvocationException("The class " + entryClass.getName() + " has no main(String[]) method.");} catch (Throwable t) {throw new ProgramInvocationException("Could not look up the main(String[]) method from the class "+ entryClass.getName() + ": " + t.getMessage(),t);}if (!Modifier.isStatic(mainMethod.getModifiers())) {throw new ProgramInvocationException("The class " + entryClass.getName() + " declares a non-static main method.");}if (!Modifier.isPublic(mainMethod.getModifiers())) {throw new ProgramInvocationException("The class " + entryClass.getName() + " declares a non-public main method.");}try {mainMethod.invoke(null, (Object) args);} catch (IllegalArgumentException e) {throw new ProgramInvocationException("Could not invoke the main method, arguments are not matching.", e);} catch (IllegalAccessException e) {throw new ProgramInvocationException("Access to the main method was denied: " + e.getMessage(), e);} catch (InvocationTargetException e) {Throwable exceptionInMethod = e.getTargetException();if (exceptionInMethod instanceof Error) {throw (Error) exceptionInMethod;} else if (exceptionInMethod instanceof ProgramParametrizationException) {throw (ProgramParametrizationException) exceptionInMethod;} else if (exceptionInMethod instanceof ProgramInvocationException) {throw (ProgramInvocationException) exceptionInMethod;} else {throw new ProgramInvocationException("The main method caused an error: " + exceptionInMethod.getMessage(),exceptionInMethod);}} catch (Throwable t) {throw new ProgramInvocationException("An error occurred while invoking the program's main method: " + t.getMessage(),t);}}private static String getEntryPointClassNameFromJar(URL jarFile)throws ProgramInvocationException {JarFile jar;Manifest manifest;String className;// Open jar filetry {jar = new JarFile(new File(jarFile.toURI()));} catch (URISyntaxException use) {throw new ProgramInvocationException("Invalid file path '" + jarFile.getPath() + "'", use);} catch (IOException ioex) {throw new ProgramInvocationException("Error while opening jar file '"+ jarFile.getPath()+ "'. "+ ioex.getMessage(),ioex);}// jar file must be closed at the endtry {// Read from jar manifesttry {manifest = jar.getManifest();} catch (IOException ioex) {throw new ProgramInvocationException("The Manifest in the jar file could not be accessed '"+ jarFile.getPath()+ "'. "+ ioex.getMessage(),ioex);}if (manifest == null) {throw new ProgramInvocationException("No manifest found in jar file '"+ jarFile.getPath()+ "'. The manifest is need to point to the program's main class.");}Attributes attributes = manifest.getMainAttributes();// check for a "program-class" entry firstclassName = attributes.getValue(PackagedProgram.MANIFEST_ATTRIBUTE_ASSEMBLER_CLASS);if (className != null) {return className;}// check for a main classclassName = attributes.getValue(PackagedProgram.MANIFEST_ATTRIBUTE_MAIN_CLASS);if (className != null) {return className;} else {throw new ProgramInvocationException("Neither a '"+ MANIFEST_ATTRIBUTE_MAIN_CLASS+ "', nor a '"+ MANIFEST_ATTRIBUTE_ASSEMBLER_CLASS+ "' entry was found in the jar file.");}} finally {try {jar.close();} catch (Throwable t) {throw new ProgramInvocationException("Could not close the JAR file: " + t.getMessage(), t);}}}@Nullableprivate static URL loadJarFile(File jar) throws ProgramInvocationException {if (jar != null) {URL jarFileUrl;try {jarFileUrl = jar.getAbsoluteFile().toURI().toURL();} catch (MalformedURLException e1) {throw new IllegalArgumentException("The jar file path is invalid.");}checkJarFile(jarFileUrl);return jarFileUrl;} else {return null;}}private static Class<?> loadMainClass(String className, ClassLoader cl)throws ProgramInvocationException {ClassLoader contextCl = null;try {contextCl = Thread.currentThread().getContextClassLoader();Thread.currentThread().setContextClassLoader(cl);return Class.forName(className, false, cl);} catch (ClassNotFoundException e) {throw new ProgramInvocationException("The program's entry point class '"+ className+ "' was not found in the jar file.",e);} catch (ExceptionInInitializerError e) {throw new ProgramInvocationException("The program's entry point class '"+ className+ "' threw an error during initialization.",e);} catch (LinkageError e) {throw new ProgramInvocationException("The program's entry point class '"+ className+ "' could not be loaded due to a linkage failure.",e);} catch (Throwable t) {throw new ProgramInvocationException("The program's entry point class '"+ className+ "' caused an exception during initialization: "+ t.getMessage(),t);} finally {if (contextCl != null) {Thread.currentThread().setContextClassLoader(contextCl);}}}/*** Takes all JAR files that are contained in this program's JAR file and extracts them to the* system's temp directory.** @return The file names of the extracted temporary files.* @throws ProgramInvocationException Thrown, if the extraction process failed.*/public static List<File> extractContainedLibraries(URL jarFile)throws ProgramInvocationException {try (final JarFile jar = new JarFile(new File(jarFile.toURI()))) {final List<JarEntry> containedJarFileEntries = getContainedJarEntries(jar);if (containedJarFileEntries.isEmpty()) {return Collections.emptyList();}final List<File> extractedTempLibraries =new ArrayList<>(containedJarFileEntries.size());boolean incomplete = true;try {final Random rnd = new Random();final byte[] buffer = new byte[4096];for (final JarEntry entry : containedJarFileEntries) {// '/' as in case of zip, jar// java.util.zip.ZipEntry#isDirectory always looks only for '/' not for// File.separatorfinal String name = entry.getName().replace('/', '_');final File tempFile = copyLibToTempFile(name, rnd, jar, entry, buffer);extractedTempLibraries.add(tempFile);}incomplete = false;} finally {if (incomplete) {deleteExtractedLibraries(extractedTempLibraries);}}return extractedTempLibraries;} catch (Throwable t) {throw new ProgramInvocationException("Unknown I/O error while extracting contained jar files.", t);}}private static File copyLibToTempFile(String name, Random rnd, JarFile jar, JarEntry input, byte[] buffer)throws ProgramInvocationException {final File output = createTempFile(rnd, input, name);try (final OutputStream out = new FileOutputStream(output);final InputStream in = new BufferedInputStream(jar.getInputStream(input))) {int numRead = 0;while ((numRead = in.read(buffer)) != -1) {out.write(buffer, 0, numRead);}return output;} catch (IOException e) {throw new ProgramInvocationException("An I/O error occurred while extracting nested library '"+ input.getName()+ "' to temporary file '"+ output.getAbsolutePath()+ "'.");}}private static File createTempFile(Random rnd, JarEntry entry, String name)throws ProgramInvocationException {try {final File tempFile = File.createTempFile(rnd.nextInt(Integer.MAX_VALUE) + "_", name);tempFile.deleteOnExit();return tempFile;} catch (IOException e) {throw new ProgramInvocationException("An I/O error occurred while creating temporary file to extract nested library '"+ entry.getName()+ "'.",e);}}private static List<JarEntry> getContainedJarEntries(JarFile jar) {return jar.stream().filter(jarEntry -> {final String name = jarEntry.getName();return name.length() > 8&& name.startsWith("lib/")&& name.endsWith(".jar");}).collect(Collectors.toList());}private static void deleteExtractedLibraries(List<File> tempLibraries) {for (File f : tempLibraries) {f.delete();}}private static void checkJarFile(URL jarfile) throws ProgramInvocationException {try {JarUtils.checkJarFile(jarfile);} catch (IOException e) {throw new ProgramInvocationException(e.getMessage(), e);} catch (Throwable t) {throw new ProgramInvocationException("Cannot access jar file"+ (t.getMessage() == null ? "." : ": " + t.getMessage()),t);}}/*** A Builder For {@link PackagedProgram}.*/public static class Builder {@Nullableprivate File jarFile;@Nullableprivate String entryPointClassName;private String[] args = new String[0];private List<URL> userClassPaths = Collections.emptyList();private Configuration configuration = new Configuration();private SavepointRestoreSettings savepointRestoreSettings = SavepointRestoreSettings.none();public Builder setJarFile(@Nullable File jarFile) {this.jarFile = jarFile;return this;}public Builder setUserClassPaths(List<URL> userClassPaths) {this.userClassPaths = userClassPaths;return this;}public Builder setEntryPointClassName(@Nullable String entryPointClassName) {this.entryPointClassName = entryPointClassName;return this;}public Builder setArguments(String... args) {this.args = args;return this;}public Builder setConfiguration(Configuration configuration) {this.configuration = configuration;return this;}public Builder setSavepointRestoreSettings(SavepointRestoreSettings savepointRestoreSettings) {this.savepointRestoreSettings = savepointRestoreSettings;return this;}public PackagedProgram build() throws ProgramInvocationException {if (jarFile == null && entryPointClassName == null) {throw new IllegalArgumentException("The jarFile and entryPointClassName can not be null at the same time.");}return new PackagedProgram(jarFile,userClassPaths,entryPointClassName,configuration,savepointRestoreSettings,args);}private Builder() {}}public static Builder newBuilder() {return new Builder();}
}

本文来自互联网用户投稿，该文观点仅代表作者本人，不代表本站立场。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如若转载，请注明出处：http://www.mzph.cn/news/654367.shtml

如若内容造成侵权/违法违规/事实不符，请联系多彩编程网进行投诉反馈email:809451989@qq.com，一经查实，立即删除！

相关文章

AOP+Redisson 延时队列，实现缓存延时双删策略

AOP+Redisson 延时队列，实现缓存延时双删策略

一、缓存延时双删 关于缓存和数据库中的数据保持一致有很多种方案&#xff0c;但不管是单独在修改数据库之前&#xff0c;还是之后去删除缓存都会有一定的风险导致数据不一致。而延迟双删是一种相对简单并且收益比较高的实现最终一致性的方式&#xff0c;即在删除缓存之后&…
阅读更多...
哪些 3D 建模软件值得推荐？

哪些 3D 建模软件值得推荐？

云端地球是一款免费的在线实景三维建模软件&#xff0c;不需要复杂的技巧&#xff0c;只要需要手机&#xff0c;多拍几张照片&#xff0c;就可以得到完整的三维模型&#xff01; 无论是大场景倾斜摄影测量还是小场景、小物体建模&#xff0c;都可以通过云端地球将二维数据向三…
阅读更多...
【JLU】校园网linux客户端运行方法

【JLU】校园网linux客户端运行方法

终于给这输入法整好了&#xff0c;就像上面图里那样执行命令就行 写一个开机自启的脚本会更方便&#xff0c;每次都运行也挺烦的 补充了一键运行脚本&#xff0c;文件路径需要自己修改 #!/bin/bashrun_per_prog"sudo /home/d0/ubuntu-drclient-64/DrClient/privillege.s…
阅读更多...
为什么3d合并的模型不能移动---模大狮模型网

为什么3d合并的模型不能移动---模大狮模型网

当你在3D软件中合并模型后&#xff0c;如果无法移动合并后的模型&#xff0c;可能有以下几个可能的原因&#xff1a; 模型被锁定或冻结&#xff1a;在3D软件中&#xff0c;你可能会将模型锁定或冻结以防止意外的移动或编辑。请确保解锁或解冻模型&#xff0c;这样你就可以自由地…
阅读更多...
学籍管理系统（c++文件实现）

学籍管理系统（c++文件实现）

要求&#xff1a; 实现增删查改&#xff0c;两种方式查询&#xff0c;登录功能 设计&#xff1a; 学生端&#xff1a;可以查询个人成绩 管理员端&#xff1a;对学籍信息增删查改&#xff0c;查看所有信息&#xff0c;单人信息&#xff0c;学籍排序&#xff0c;统计绩点 三个…
阅读更多...
【Python】采用OpenCV和Flask来进行网络图像推流的低延迟高刷FPS方法（项目模板）

【Python】采用OpenCV和Flask来进行网络图像推流的低延迟高刷FPS方法（项目模板）

【Python】采用OpenCV和Flask来进行网络图像推流的低延迟高刷FPS方法&#xff08;项目模板&#xff09; gitee项目模板&#xff1a; 网络图像推流项目模板&#xff08;采用OpenCV和Flask来进行网络图像推流的低延迟高刷FPS方法&#xff09; 前文&#xff1a; 【最简改进】基于…
阅读更多...
伊恩·斯图尔特《改变世界的17个方程》相对论笔记

伊恩·斯图尔特《改变世界的17个方程》相对论笔记

它告诉我们什么&#xff1f; 物质包含的能量等于其质量乘以光速的平方。 为什么重要&#xff1f; 光的速度很快&#xff0c;它的平方绝对是一个巨大的数。1千克的物质释放出的能量相当于史上最大的核武器爆炸所释放能量的约40%。一系列相关的方程改变了我们对空间、时间、物质和…
阅读更多...
字符串二叉树遍历

字符串二叉树遍历

假定一棵二叉树的每个结点都用一个大写字母描述。给定这棵二叉树的前序遍历和中序遍历&#xff0c;求其后序遍历。 输入格式 输入包含多组测试数据。每组数据占两行&#xff0c;每行包含一个大写字母构成的字符串&#xff0c;第一行表示二叉树的前序遍历&#xff0c;第二行表示…
阅读更多...
Prompt Learning 的几个重点paper

Prompt Learning 的几个重点paper

Prefix Tuning: Prefix-Tuning: Optimizing Continuous Prompts for Generation 在输入token之前构造一段任务相关的virtual tokens作为Prefix&#xff0c;然后训练的时候只更新Prefix部分的参数&#xff0c;PLM中的其他参数固定。针对自回归架构模型&#xff1a;在句子前面添…
阅读更多...
测试的常用工具介绍，Fiddler、Postman、JMeter

测试的常用工具介绍，Fiddler、Postman、JMeter

前言 大家好&#xff0c;我是chowley&#xff0c;今天介绍几个在软件测试领域比较常用的测试工具。 本文将介绍三种常用的测试工具&#xff1a;Fiddler、Postman、JMeter&#xff0c;它们分别在不同测试场景下展现了强大的功能和灵活性。 测试工具 在软件开发和测试领域&am…
阅读更多...
vue 使用echarts-gl实现3d旋转地图

vue 使用echarts-gl实现3d旋转地图

之前也有使用过echarts开发项目中涉及到的地图功能&#xff0c;当时使用geo来实现地图轮廓&#xff0c;看上去有种3d的感觉。最近闲来无事看了一份可视化大屏的UI设计图&#xff0c;感觉3d旋转地图挺好玩的&#xff0c;今天就来尝试实现下。 首先安装下echarts和echarts-gl依赖…
阅读更多...
MyBatis框架-配置解析

MyBatis框架-配置解析

文章目录 Mybatis配置解析核心配置文件environments 环境配置transactionManager 事务管理器dataSource 数据源mappers 映射器Mapper文件Properties优化类型别名&#xff08;typeAliases&#xff09;setting类型处理器&#xff08;typeHandlers&#xff09;对象工厂&#xff08…
阅读更多...
shell脚本——条件语句

shell脚本——条件语句

目录 一、条件语句 1、test命令测试条件表达式 2、整数数值比较 3、字符串比较 4、逻辑测试&#xff08;短路运算&#xff09; 5、双中括号 二、if语句 1、 分支结构 1.1 单分支结果 1.2 双分支 1.3 多分支 2、case 一、条件语句 条件测试&#xff1a;判断某需求是…
阅读更多...
MySQL事务和锁02

MySQL事务和锁02

官网地址&#xff1a;MySQL :: MySQL 5.7 Reference Manual :: 13.3.2 Statements That Cannot Be Rolled Back 欢迎关注留言&#xff0c;我是收集整理小能手&#xff0c;工具翻译&#xff0c;仅供参考&#xff0c;笔芯笔芯. Mysql5.7参考手册 / ... / 不能回滚的语句 13.…
阅读更多...
1002. HarmonyOS 开发问题：鸿蒙 OS 技术特性是什么?

1002. HarmonyOS 开发问题：鸿蒙 OS 技术特性是什么?

1002. HarmonyOS 开发问题&#xff1a;鸿蒙 OS 技术特性是什么? 硬件互助&#xff0c;资源共享 分布式软总线 分布式软总线是多种终端设备的统一基座&#xff0c;为设备之间的互联互通提供了统一的分布式通信能力&#xff0c;能够快速发现并连接设备&#xff0c;高效地分发…
阅读更多...
计算机网络——网络层（2）

计算机网络——网络层（2）

计算机网络——网络层&#xff08;2&#xff09; 小程一言专栏链接: [link](http://t.csdnimg.cn/ZUTXU) 网络层——控制平面概述路由选择转发表路由协议路由信息的交换小结 路由选择算法常见的路由选择算法距离矢量路由算法工作原理优缺点分析 链路状态路由算法基本工作原理优…
阅读更多...
【Java 设计模式】行为型之迭代器模式

【Java 设计模式】行为型之迭代器模式

文章目录 1. 定义2. 应用场景3. 代码实现结语 迭代器模式&#xff08;Iterator Pattern&#xff09;是一种行为型设计模式&#xff0c;用于提供一种顺序访问聚合对象中各个元素的方法&#xff0c;而不暴露聚合对象的内部表示。迭代器模式将遍历聚合对象的责任分离出来&#xff…
阅读更多...
【详解】贪吃蛇游戏----下篇（完整源码）

【详解】贪吃蛇游戏----下篇（完整源码）

目录 引入&#xff1a; 本片文章目的&#xff1a; 整个游戏的实现流程图如下&#xff1a; 游戏实现 GameRun PrintHelpInfo Pause NextIsFood printSnake EatFood NoFood KillByWall KillBySelf GameRun GameEnd 总代码&#xff1a; &#xff08;1&#xff09…
阅读更多...
pcie基础知识

pcie基础知识

文章目录 总线PCIEPCIE对应版本速率pcie拓扑linux查看pcie设备PCIE配置空间BAR&#xff08;基地址寄存器&#xff09; 总线 什么是总线 总线就是电脑内部交互的通道。 最开始CPU连接声卡或者网卡用的是不同接口&#xff0c;比如你声卡坏了&#xff0c;换一个声卡&#xff0c;接…
阅读更多...
二叉搜索树操作题目：二叉搜索树中的插入操作

二叉搜索树操作题目：二叉搜索树中的插入操作

文章目录 题目标题和出处难度题目描述要求示例数据范围 解法一思路和算法代码复杂度分析 解法二思路和算法代码复杂度分析 题目 标题和出处 标题&#xff1a;二叉搜索树中的插入操作 出处&#xff1a;701. 二叉搜索树中的插入操作 难度 3 级 题目描述 要求 给定二叉搜索…
阅读更多...
最新文章

Copyright @ 2022~2023