feat: Add Java Module (#314)

Implements a Java module which shows basic Java information when inside a Java project.

.github/workflows/continuous-integration.yml

@@ -71,6 +71,11 @@ jobs:
         with:
           python-version: "3.6.9"
       
+      # Install Java at a fixed version
+      - uses: actions/setup-java@master
+        with:
+          java-version: '12.0.2'
+
       # Run the ignored tests that expect the above setup
       - uses: actions/checkout@master
       - name: Run all tests

Cargo.lock

@@ -2,10 +2,10 @@
 # It is not intended for manual editing.
 [[package]]
 name = "aho-corasick"
-version = "0.7.3"
+version = "0.7.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "memchr 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -255,7 +255,7 @@ dependencies = [
  "atty 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "humantime 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex 1.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "termcolor 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -408,7 +408,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "memchr"
-version = "2.2.0"
+version = "2.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -638,23 +638,19 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.1.6"
+version = "1.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "aho-corasick 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "aho-corasick 0.7.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "memchr 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex-syntax 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex-syntax 0.6.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "utf8-ranges 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "regex-syntax"
-version = "0.6.6"
+version = "0.6.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "ucd-util 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
-]
 
 [[package]]
 name = "remove_dir_all"
@@ -844,11 +840,6 @@ name = "typenum"
 version = "1.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "ucd-util"
-version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "unicode-bidi"
 version = "0.3.4"
@@ -899,11 +890,6 @@ dependencies = [
  "percent-encoding 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "utf8-ranges"
-version = "1.0.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "vcpkg"
 version = "0.2.6"
@@ -961,7 +947,7 @@ dependencies = [
 ]
 
 [metadata]
-"checksum aho-corasick 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)" = "e6f484ae0c99fec2e858eb6134949117399f222608d84cadb3f58c1f97c2364c"
+"checksum aho-corasick 0.7.6 (registry+https://github.com/rust-lang/crates.io-index)" = "58fb5e95d83b38284460a5fda7d6470aa0b8844d283a0b614b8535e880800d2d"
 "checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
 "checksum ansi_term 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d52a9bb7ec0cf484c551830a7ce27bd20d67eac647e1befb56b0be4ee39a55d2"
 "checksum argon2rs 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)" = "3f67b0b6a86dae6e67ff4ca2b6201396074996379fba2b92ff649126f37cb392"
@@ -1008,7 +994,7 @@ dependencies = [
 "checksum log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)" = "14b6052be84e6b71ab17edffc2eeabf5c2c3ae1fdb464aae35ac50c67a44e1f7"
 "checksum mach 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "86dd2487cdfea56def77b88438a2c915fb45113c5319bfe7e14306ca4cd0b0e1"
 "checksum matches 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "7ffc5c5338469d4d3ea17d269fa8ea3512ad247247c30bd2df69e68309ed0a08"
-"checksum memchr 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2efc7bc57c883d4a4d6e3246905283d8dae951bb3bd32f49d6ef297f546e1c39"
+"checksum memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "88579771288728879b57485cc7d6b07d648c9f0141eb955f8ab7f9d45394468e"
 "checksum memoffset 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ce6075db033bbbb7ee5a0bbd3a3186bbae616f57fb001c485c7ff77955f8177f"
 "checksum nix 0.14.0 (registry+https://github.com/rust-lang/crates.io-index)" = "0d10caafde29a846a82ae0af70414e4643e072993441033b2c93217957e2f867"
 "checksum nodrop 0.1.13 (registry+https://github.com/rust-lang/crates.io-index)" = "2f9667ddcc6cc8a43afc9b7917599d7216aa09c463919ea32c59ed6cac8bc945"
@@ -1038,8 +1024,8 @@ dependencies = [
 "checksum redox_syscall 0.1.54 (registry+https://github.com/rust-lang/crates.io-index)" = "12229c14a0f65c4f1cb046a3b52047cdd9da1f4b30f8a39c5063c8bae515e252"
 "checksum redox_termios 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7e891cfe48e9100a70a3b6eb652fef28920c117d366339687bd5576160db0f76"
 "checksum redox_users 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3fe5204c3a17e97dde73f285d49be585df59ed84b50a872baf416e73b62c3828"
-"checksum regex 1.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "8f0a0bcab2fd7d1d7c54fa9eae6f43eddeb9ce2e7352f8518a814a4f65d60c58"
+"checksum regex 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "dc220bd33bdce8f093101afe22a037b8eb0e5af33592e6a9caafff0d4cb81cbd"
-"checksum regex-syntax 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)" = "dcfd8681eebe297b81d98498869d4aae052137651ad7b96822f09ceb690d0a96"
+"checksum regex-syntax 0.6.12 (registry+https://github.com/rust-lang/crates.io-index)" = "11a7e20d1cce64ef2fed88b66d347f88bd9babb82845b2b858f3edbf59a4f716"
 "checksum remove_dir_all 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3488ba1b9a2084d38645c4c08276a1752dcbf2c7130d74f1569681ad5d2799c5"
 "checksum rustc-demangle 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)" = "ccc78bfd5acd7bf3e89cffcf899e5cb1a52d6fafa8dec2739ad70c9577a57288"
 "checksum rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
@@ -1062,7 +1048,6 @@ dependencies = [
 "checksum time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)" = "db8dcfca086c1143c9270ac42a2bbd8a7ee477b78ac8e45b19abfb0cbede4b6f"
 "checksum toml 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)" = "c7aabe75941d914b72bf3e5d3932ed92ce0664d49d8432305a8b547c37227724"
 "checksum typenum 1.10.0 (registry+https://github.com/rust-lang/crates.io-index)" = "612d636f949607bdf9b123b4a6f6d966dedf3ff669f7f045890d3a4a73948169"
-"checksum ucd-util 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "535c204ee4d8434478593480b8f86ab45ec9aae0e83c568ca81abf0fd0e88f86"
 "checksum unicode-bidi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "49f2bd0c6468a8230e1db229cff8029217cf623c767ea5d60bfbd42729ea54d5"
 "checksum unicode-normalization 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "141339a08b982d942be2ca06ff8b076563cbe223d1befd5450716790d44e2426"
 "checksum unicode-segmentation 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1967f4cdfc355b37fd76d2a954fb2ed3871034eb4f26d60537d88795cfc332a9"
@@ -1070,7 +1055,6 @@ dependencies = [
 "checksum unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fc72304796d0818e357ead4e000d19c9c174ab23dc11093ac919054d20a6a7fc"
 "checksum uom 0.23.0 (registry+https://github.com/rust-lang/crates.io-index)" = "347fe3ff20637a62ab9749a5c90d167302bcbdab77ec961dda7f62a5ca6d368a"
 "checksum url 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "77ddaf52e65c6b81c56b7e957c0b1970f7937f21c5c6774c4e56fcb4e20b48c6"
-"checksum utf8-ranges 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "796f7e48bef87609f7ade7e06495a87d5cd06c7866e6a5cbfceffc558a243737"
 "checksum vcpkg 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "def296d3eb3b12371b2c7d0e83bfe1403e4db2d7a0bba324a12b21c4ee13143d"
 "checksum vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "05c78687fb1a80548ae3250346c3db86a80a7cdd77bda190189f2d0a0987c81a"
 "checksum void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"

README.md

@@ -59,6 +59,7 @@ The prompt shows information you need while you're working, while staying sleek
 
 - Prompt character turns red if the last command exits with non-zero code
 - Current username if not the same as the logged-in user
+- Current Java version(`☕`)
 - Current Node.js version(`⬢`)
 - Current Rust version (`🦀`)
 - Current Ruby version (`💎`)

docs/config/README.md

@@ -93,6 +93,7 @@ prompt_order = [
     "rust",
     "python",
     "golang",
+    "java",
     "nix_shell",
     "cmd_duration",
     "line_break",
@@ -493,6 +494,31 @@ impure_msg = "impure shell"
 pure_msg = "pure shell"
 ```
 
+## Java
+
+The `java` module shows the currently installed version of Java.
+The module will be shown if any of the following conditions are met:
+
+- The current directory contains a `pom.xml` or `build.gradle` file
+- The current directory contains a file with the `.java`, `.class` or `.jar` extension
+
+### Options
+
+| Variable   | Default        | Description                                              |
+| ---------- | -------------- | -------------------------------------------------------- |
+| `symbol`   | `"☕ "`         | The symbol used before displaying the version of Java.  |
+| `style`    | `"dimmed red"` | The style for the module.                               |
+| `disabled` | `false`        | Disables the `java` module.                              |
+
+### Example
+
+```toml
+# ~/.config/starship.toml
+
+[java]
+symbol = "🌟 "
+```
+
 
 ## NodeJS
 

src/module.rs

@@ -16,6 +16,7 @@ pub const ALL_MODULES: &[&str] = &[
     "git_status",
     "golang",
     "hostname",
+    "java",
     "jobs",
     "line_break",
     "nix_shell",

src/modules/java.rs

@@ -0,0 +1,105 @@
+use std::process::Command;
+
+use ansi_term::Color;
+
+use super::{Context, Module};
+
+/// Creates a module with the current Java version
+///
+/// Will display the Java version if any of the following criteria are met:
+///     - Current directory contains a file with a `.java`, `.class` or `.jar` extension
+///     - Current directory contains a `pom.xml` or `build.gradle` file
+pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
+    let is_java_project = context
+        .try_begin_scan()?
+        .set_files(&["pom.xml", "build.gradle"])
+        .set_extensions(&["java", "class", "jar"])
+        .is_match();
+
+    if !is_java_project {
+        return None;
+    }
+
+    match get_java_version() {
+        Some(java_version) => {
+            const JAVA_CHAR: &str = "☕ ";
+
+            let mut module = context.new_module("java");
+            let module_style = module
+                .config_value_style("style")
+                .unwrap_or_else(|| Color::Red.dimmed());
+            module.set_style(module_style);
+
+            let formatted_version = format_java_version(java_version)?;
+            module.new_segment("symbol", JAVA_CHAR);
+            module.new_segment("version", &formatted_version);
+
+            Some(module)
+        }
+        None => None,
+    }
+}
+
+fn get_java_version() -> Option<String> {
+    let java_command = match std::env::var("JAVA_HOME") {
+        Ok(java_home) => format!("{}/bin/java", java_home),
+        Err(_) => String::from("java"),
+    };
+
+    match Command::new(java_command).arg("-Xinternalversion").output() {
+        Ok(output) => Some(String::from_utf8(output.stdout).unwrap()),
+        Err(_) => None,
+    }
+}
+
+/// Extract the java version from `java_stdout`.
+/// The expected format is similar to: "JRE (1.8.0_222-b10)".
+/// Some Java vendors don't follow this format: "JRE (Zulu 8.40.0.25-CA-linux64)").
+fn format_java_version(java_stdout: String) -> Option<String> {
+    let start = java_stdout.find("JRE (")? + "JRE (".len();
+    let end = start
+        + (java_stdout[start..].find(|c| match c {
+            '0'..='9' | '.' => false,
+            _ => true,
+        })?);
+
+    if start == end {
+        None
+    } else {
+        Some(format!("v{}", &java_stdout[start..end]))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_format_java_version_openjdk() {
+        let java_8 = String::from("OpenJDK 64-Bit Server VM (25.222-b10) for linux-amd64 JRE (1.8.0_222-b10), built on Jul 11 2019 10:18:43 by \"openjdk\" with gcc 4.4.7 20120313 (Red Hat 4.4.7-23)");
+        let java_11 = String::from("OpenJDK 64-Bit Server VM (11.0.4+11-post-Ubuntu-1ubuntu219.04) for linux-amd64 JRE (11.0.4+11-post-Ubuntu-1ubuntu219.04), built on Jul 18 2019 18:21:46 by \"build\" with gcc 8.3.0");
+        assert_eq!(format_java_version(java_11), Some(String::from("v11.0.4")));
+        assert_eq!(format_java_version(java_8), Some(String::from("v1.8.0")));
+    }
+
+    #[test]
+    fn test_format_java_version_oracle() {
+        let java_8 = String::from("Java HotSpot(TM) Client VM (25.65-b01) for linux-arm-vfp-hflt JRE (1.8.0_65-b17), built on Oct  6 2015 16:19:04 by \"java_re\" with gcc 4.7.2 20120910 (prerelease)");
+        assert_eq!(format_java_version(java_8), Some(String::from("v1.8.0")));
+    }
+
+    #[test]
+    fn test_format_java_version_redhat() {
+        let java_8 = String::from("OpenJDK 64-Bit Server VM (25.222-b10) for linux-amd64 JRE (1.8.0_222-b10), built on Jul 11 2019 20:48:53 by \"root\" with gcc 7.3.1 20180303 (Red Hat 7.3.1-5)");
+        let java_12 = String::from("OpenJDK 64-Bit Server VM (12.0.2+10) for linux-amd64 JRE (12.0.2+10), built on Jul 18 2019 14:41:47 by \"jenkins\" with gcc 7.3.1 20180303 (Red Hat 7.3.1-5)");
+        assert_eq!(format_java_version(java_8), Some(String::from("v1.8.0")));
+        assert_eq!(format_java_version(java_12), Some(String::from("v12.0.2")));
+    }
+
+    #[test]
+    fn test_format_java_version_zulu() {
+        // Not currently supported
+        let java_8 = String::from("OpenJDK 64-Bit Server VM (25.222-b10) for linux-amd64 JRE (Zulu 8.40.0.25-CA-linux64) (1.8.0_222-b10), built on Jul 11 2019 11:36:39 by \"zulu_re\" with gcc 4.4.7 20120313 (Red Hat 4.4.7-3)");
+        assert_eq!(format_java_version(java_8), None);
+    }
+}

src/modules/mod.rs

@@ -7,6 +7,7 @@ mod git_state;
 mod git_status;
 mod golang;
 mod hostname;
+mod java;
 mod jobs;
 mod line_break;
 mod nix_shell;
@@ -42,6 +43,7 @@ pub fn handle<'a>(module: &str, context: &'a Context) -> Option<Module<'a>> {
         #[cfg(feature = "battery")]
         "battery" => battery::module(context),
         "cmd_duration" => cmd_duration::module(context),
+        "java" => java::module(context),
         "jobs" => jobs::module(context),
         "nix_shell" => nix_shell::module(context),
         "hostname" => hostname::module(context),

src/print.rs

@@ -24,6 +24,7 @@ const DEFAULT_PROMPT_ORDER: &[&str] = &[
     "rust",
     "python",
     "golang",
+    "java",
     "nix_shell",
     "cmd_duration",
     "line_break",

tests/Dockerfile

@@ -48,6 +48,23 @@ RUN curl https://pyenv.run | bash \
 # Check that Python was correctly installed
 RUN python --version
 
+# Install Java.
+ENV JAVA_HOME /home/nonroot/java
+ENV PATH $JAVA_HOME/bin:$PATH
+ENV JAVA_URL https://download.java.net/java/GA/jdk12.0.2/e482c34c86bd4bf8b56c0b35558996b9/10/GPL/openjdk-12.0.2_linux-x64_bin.tar.gz
+
+RUN mkdir -p "$JAVA_HOME"; \
+RUN set -eux; \
+	curl -fL -o $JAVA_HOME/openjdk.tgz "$JAVA_URL"; \
+	tar --extract \
+		--file $JAVA_HOME/openjdk.tgz \
+		--directory "$JAVA_HOME" \
+		--strip-components 1 \
+		--no-same-owner \
+	; \
+RUN java -version; \
+    javac -version
+
 # Create blank project
 RUN USER=nonroot cargo new --bin /src/starship
 WORKDIR /src/starship

tests/testsuite/java.rs

@@ -0,0 +1,26 @@
+use std::fs::File;
+use std::io;
+
+use ansi_term::Color;
+
+use crate::common;
+
+// When these tests run in the CI, they use Azul's Zulu Java distribution.
+// The version format returned by this java package is irregular and not supported (yet).
+
+//#[test]
+//#[ignore]
+//fn folder_with_pom() -> io::Result<()> {
+//    let dir = common::new_tempdir()?;
+//    File::create(dir.path().join("pom.xml"))?;
+//
+//    let output = common::render_module("java")
+//        .arg("--path")
+//        .arg(dir.path())
+//        .output()?;
+//    let actual = String::from_utf8(output.stdout).unwrap();
+//
+//    let expected = format!("via {} ", Color::Red.dimmed().paint("☕ "));
+//    assert_eq!(expected, actual);
+//    Ok(())
+//}

tests/testsuite/main.rs

@@ -8,6 +8,7 @@ mod git_state;
 mod git_status;
 mod golang;
 mod hostname;
+mod java;
 mod jobs;
 mod line_break;
 mod modules;