1、到github下载源码
查找地址：https://github.com/spring-projects/spring-framework/tree/5.0.x
下载地址：https://codeload.github.com/spring-projects/spring-framework/zip/5.0.x
2、将源码包解压，并查看 import-into-idea.md 文件（非常重要），按文件步骤进行操作
1）、在源码包下，打开命名窗口，执行gradlew :spring-oxm:compileTestJava`命令，命令执行后，会默认下载Gradle4.4.1版本，并保存到默认目录C:\Users\Administrator\.gradle\wrapper\dists\gradle-4.4.1-bin\46gopw3g8i1v3zqqx4q949t2x\gradle-4.4.1下。
2）、执行命令完毕后，打开IDEA ->File->New->Project from Existing Sources -> Navigate to directory(找到目录) -> Select build.gradle（选择build.gradle文件），会弹出如下配置页面
配置完上图标注几项即可，其中可以使用Use default gradle wrapper 选项，也可以选择Use local gradle distribution,若选择了第二项，则需要到gradle默认目录下，找到gradle-4.4.1，配置完后等待编译即可
3、在编译完之后，运行会遇到几个为
1）、运行时报Error:Kotlin: [Internal Error] java.lang.AbstractMethodError: org.jetbrains.这个错误。具体错误内容如下
Error:Kotlin: [Internal Error] java.lang.IllegalStateException: The provided plugin org.jetbrains.kotlin.scripting.compiler.plugin.ScriptingCompilerConfigurationComponentRegistrar is not compatible with this version of compiler at org.jetbrains.kotlin.cli.jvm.compiler.KotlinCoreEnvironment.<init>(KotlinCoreEnvironment.kt:181) at org.jetbrains.kotlin.cli.jvm.compiler.KotlinCoreEnvironment.<init>(KotlinCoreEnvironment.kt:117) at org.jetbrains.kotlin.cli.jvm.compiler.KotlinCoreEnvironment$Companion.createForProduction(KotlinCoreEnvironment.kt:413) at org.jetbrains.kotlin.cli.jvm.K2JVMCompiler.createCoreEnvironment(K2JVMCompiler.kt:276) at org.jetbrains.kotlin.cli.jvm.K2JVMCompiler.doExecute(K2JVMCompiler.kt:154) at org.jetbrains.kotlin.cli.jvm.K2JVMCompiler.doExecute(K2JVMCompiler.kt:63) at org.jetbrains.kotlin.cli.common.CLICompiler.execImpl(CLICompiler.java:108) at org.jetbrains.kotlin.cli.common.CLICompiler.execImpl(CLICompiler.java:52) at org.jetbrains.kotlin.cli.common.CLITool.exec(CLITool.kt:92) at org.jetbrains.kotlin.daemon.CompileServiceImpl$compile
inlined$ifAlive$lambda$1.invoke(CompileServiceImpl.kt:389)atorg.jetbrains.kotlin.daemon.CompileServiceImpl$compile
inlined$ifAlive$lambda$1.invoke(CompileServiceImpl.kt:389)atorg.jetbrains.kotlin.daemon.CompileServiceImpl$compile
inlined$ifAlive$lambda$1.invoke(CompileServiceImpl.kt:97) at org.jetbrains.kotlin.daemon.CompileServiceImpl$doCompile
inlined$ifAlive$lambda$2.invoke(CompileServiceImpl.kt:909)atorg.jetbrains.kotlin.daemon.CompileServiceImpl$doCompile
inlined$ifAlive$lambda$2.invoke(CompileServiceImpl.kt:909)atorg.jetbrains.kotlin.daemon.CompileServiceImpl$doCompile
inlined$ifAlive$lambda$2.invoke(CompileServiceImpl.kt:97) at org.jetbrains.kotlin.daemon.common.DummyProfiler.withMeasure(PerfUtils.kt:137) at org.jetbrains.kotlin.daemon.CompileServiceImpl.checkedCompile(CompileServiceImpl.kt:939) at org.jetbrains.kotlin.daemon.CompileServiceImpl.doCompile(CompileServiceImpl.kt:908) at org.jetbrains.kotlin.daemon.CompileServiceImpl.compile(CompileServiceImpl.kt:387) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:324) at sun.rmi.transport.Transport$1.run(Transport.java:200) at sun.rmi.transport.Transport$1.run(Transport.java:197) at java.security.AccessController.doPrivileged(Native Method) at sun.rmi.transport.Transport.serviceCall(Transport.java:196) at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:568) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:826) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:683) at java.security.AccessController.doPrivileged(Native Method) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:682) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) Caused by: java.lang.AbstractMethodError: org.jetbrains.kotlin.scripting.compiler.plugin.ScriptingCompilerConfigurationComponentRegistrar.registerProjectComponents(Lcom/intellij/mock/MockProject;Lorg/jetbrains/kotlin/config/CompilerConfiguration;)V at org.jetbrains.kotlin.cli.jvm.compiler.KotlinCoreEnvironment.<init>(KotlinCoreEnvironment.kt:179) ... 33 more
这是kotlin版本的问题，在idea 工具中File->Settings->Plugins->Kotlin,点击Update后重启IDEA就可以了.
2)、build时，spring-core报错，缺失DefaultNamingPolicy类，它来源于spring-cglib-repack、spring-objenesis-repack这两个jar文件。
解决方法：
进入源码的目录，执行：gradlew objenesisRepackJar 、 gradlew cglibRepackJar
完毕