基本任务

本页介绍在您设置好项目后如何使用 sbt。本页假定您已阅读 sbt 组件。

如果您拉取使用 sbt 的仓库，上手相当容易。首先，从 GitHub 或其他仓库获取包。

$ git clone https://github.com/scalanlp/breeze.git
$ cd breeze

使用 sbtn 的 sbt shell

如 sbt 组件 所述，启动 sbt shell：

$ sbt

这应该会显示类似以下的内容：

$ sbt
[info] entering *experimental* thin client - BEEP WHIRR
[info] server was not detected. starting an instance
[info] welcome to sbt 1.5.5 (Azul Systems, Inc. Java 1.8.0_352)
[info] loading global plugins from /Users/eed3si9n/.sbt/1.0/plugins
[info] loading settings for project breeze-build from plugins.sbt ...
[info] loading project definition from /private/tmp/breeze/project
Downloading https://repo1.maven.org/maven2/org/scalanlp/sbt-breeze-expand-codegen_2.12_1.0/0.2.1/sbt-breeze-expand-codegen-0.2.1.pom
....
[info] sbt server started at local:///Users/eed3si9n/.sbt/1.0/server/dd982e07e85c7de1b618/sock
[info] terminate the server with `shutdown`
[info] disconnect from the server with `exit`
sbt:breeze-parent>

projects 命令

让我们使用 projects 命令列出子项目来探索构建：

sbt:breeze-parent> projects
[info] In file:/private/tmp/breeze/
[info]     benchmark
[info]     macros
[info]     math
[info]     natives
[info]   * root
[info]     viz

这表明该构建有 6 个子项目，包括名为 root 的当前子项目。

tasks 命令

同样，我们可以使用 tasks 命令列出该构建可用的任务：

sbt:breeze-parent> tasks

This is a list of tasks defined for the current project.
It does not list the scopes the tasks are defined in; use the 'inspect' command for that.
Tasks produce values.  Use the 'show' command to run the task and print the resulting value.

  bgRun            Start an application's default main class as a background job
  bgRunMain        Start a provided main class as a background job
  clean            Deletes files produced by the build, such as generated sources, compiled classes, and task caches.
  compile          Compiles sources.
  console          Starts the Scala interpreter with the project classes on the classpath.
  consoleProject   Starts the Scala interpreter with the sbt and the build definition on the classpath and useful imports.
  consoleQuick     Starts the Scala interpreter with the project dependencies on the classpath.
  copyResources    Copies resources to the output directory.
  doc              Generates API documentation.
  package          Produces the main artifact, such as a binary jar.  This is typically an alias for the task that actually does the packaging.
  packageBin       Produces a main artifact, such as a binary jar.
  packageDoc       Produces a documentation artifact, such as a jar containing API documentation.
  packageSrc       Produces a source artifact, such as a jar containing sources and resources.
  publish          Publishes artifacts to a repository.
  publishLocal     Publishes artifacts to the local Ivy repository.
  publishM2        Publishes artifacts to the local Maven repository.
  run              Runs a main class, passing along arguments provided on the command line.
  runMain          Runs the main class selected by the first argument, passing the remaining arguments to the main method.
  test             Executes all tests.
  testOnly         Executes the tests provided as arguments or all tests if no arguments are provided.
  testQuick        Executes the tests that either failed before, were not run or whose transitive dependencies changed, among those provided as arguments.
  update           Resolves and optionally retrieves dependencies, producing a report.

More tasks may be viewed by increasing verbosity.  See 'help tasks'

compile

compile 任务在解析并下载库依赖后编译源代码。

> compile

这应该会显示类似以下的内容：

sbt:breeze-parent> compile
[info] compiling 341 Scala sources and 1 Java source to /private/tmp/breeze/math/target/scala-3.1.3/classes ...
  | => math / Compile / compileIncremental 51s

run

run 任务运行子项目的主类。在 sbt shell 中，输入 math/run：

> math/run

math/run 表示作用于 math 子项目的 run 任务。这应该会显示类似以下的内容：

sbt:breeze-parent> math/run
[info] Scala version: 3.1.3 true
....

Multiple main classes detected. Select one to run:
 [1] breeze.optimize.linear.NNLS
 [2] breeze.optimize.proximal.NonlinearMinimizer
 [3] breeze.optimize.proximal.QuadraticMinimizer
 [4] breeze.util.UpdateSerializedObjects

Enter number:

在提示符处输入 1。

test

test 任务会运行之前失败、未运行或传递依赖发生变化的测试。

> math/test

这应该会显示类似以下的内容：

sbt:breeze-parent> math/testQuick
[info] FeatureVectorTest:
[info] - axpy fv dv (1 second, 106 milliseconds)
[info] - axpy fv vb (9 milliseconds)
[info] - DM mult (19 milliseconds)
[info] - CSC mult (32 milliseconds)
[info] - DM trans mult (4 milliseconds)
....
[info] Run completed in 58 seconds, 183 milliseconds.
[info] Total number of tests run: 1285
[info] Suites: completed 168, aborted 0
[info] Tests: succeeded 1285, failed 0, canceled 0, ignored 0, pending 0
[info] All tests passed.
[success] Total time: 130 s (02:10), completed Feb 19, 2024

Watch（波浪号）命令

为了加快您的编辑-编译-测试循环，您可以让 sbt 在您保存源文件时自动重新编译或运行测试。

在命令前加上 ~ 前缀，可在一个或多个源文件发生变化时运行该命令。例如，在 sbt shell 中尝试：

> ~test

按回车键停止监视更改。您可以在 sbt shell 或批处理模式中使用 ~ 前缀。