fix(run): run JAR Applications on the project JDK by default

A JAR Application without a chosen JRE ran `java` from PATH even with a
Project JDK set. Its default JRE is now the project JDK, applied with the
other toolchains and left out when saving so it follows later changes.

crates/ide-sdk/src/apply.rs

@@ -1620,6 +1620,17 @@ pub fn apply_to_run_configs_in(configs: &mut [RunConfig], root: &Path, fallback:
                     path_dirs.push(bin);
                 }
             }
+            // JAR Application's default JRE is the project JDK; a chosen JRE is an absolute `java`.
+            "jar-application" => {
+                if let Some(jdk) = &jdk
+                    && c.command == "java"
+                {
+                    let java = crate::java::java_executable(&jdk.home);
+                    if java.is_file() {
+                        c.command = java.to_string_lossy().into_owned();
+                    }
+                }
+            }
             "tomcat" => {
                 if let Some(jdk) = &jdk {
                     c.env.entry("JAVA_HOME".into()).or_insert_with(|| jdk.home.to_string_lossy().into_owned());

crates/ide-sdk/src/tests.rs

@@ -383,6 +383,30 @@ fn fake_jdk(dir: &Path) {
     std::fs::write(dir.join("bin").join(crate::exe("javac")), "").unwrap();
 }
 
+#[test]
+fn jar_application_runs_on_the_project_jdk_unless_a_jre_is_chosen() {
+    let tmp = tempfile::tempdir().unwrap();
+    let jdk = tmp.path().join("jbr");
+    fake_jdk(&jdk);
+    let mut s = Settings::default();
+    let mut configs = vec![run("jar-application", "java", &["-jar", "app.jar"])];
+    apply_to_run_configs(&mut configs, tmp.path(), &s);
+    assert_eq!(configs[0].command, "java", "java on PATH without a project JDK");
+
+    s.languages.java.jdk = jdk.to_string_lossy().into_owned();
+    let chosen = tmp.path().join("other/bin/java").to_string_lossy().into_owned();
+    let mut configs = vec![
+        run("jar-application", "java", &["-jar", "app.jar"]),
+        run("jar-application", &chosen, &["-jar", "app.jar"]),
+    ];
+    apply_to_run_configs(&mut configs, tmp.path(), &s);
+    let java = crate::java::java_executable(&project_jdk(tmp.path(), &s).unwrap().home).to_string_lossy().into_owned();
+    assert_eq!(configs[0].command, java);
+    assert_eq!(configs[1].command, chosen, "an explicit JRE stays");
+    // Saved as the default, so it follows a later Project JDK change.
+    assert_eq!(without_derived(&configs[0], tmp.path(), &s).command, "java");
+}
+
 #[test]
 fn project_jdk_and_maven_settings() {
     if cfg!(windows) {

src/features/run/jvmTypes.ts

@@ -188,7 +188,7 @@ export const jarApplicationType: RunConfigTypeContribution = {
     { key: "jarPath", label: "Path to JAR", mono: true, required: true, browse: "file" },
     vmOptionsField(),
     { key: "programArgs", label: "Program arguments", mono: true },
-    { ...jreField, options: [{ value: "", label: "Default (java on PATH)" }] },
+    { ...jreField, options: [{ value: "", label: "Default (the project's JDK)" }] },
   ],
   commandLine(p) {
     return {

src/platform/locales/text/en.json

@@ -215,7 +215,7 @@
   "JAR Application": "JAR Application",
   "Run an executable JAR": "Run an executable JAR",
   "Path to JAR": "Path to JAR",
-  "Default (java on PATH)": "Default (java on PATH)",
+  "Default (the project's JDK)": "Default (the project's JDK)",
   "Stream Sample TUI": "Stream Sample TUI",
   "Arduino tool '{configured}' was not found. Set its path in Settings > Languages & Frameworks > Language Servers, or in settings.toml under languages.arduino.": "Arduino tool '{configured}' was not found. Set its path in Settings > Languages & Frameworks > Language Servers, or in settings.toml under languages.arduino.",
   "Arduino tool '{name}' was not found on PATH or in Arduino IDE. Install Arduino IDE 2, or set its path in Settings > Languages & Frameworks > Language Servers or settings.toml under languages.arduino.": "Arduino tool '{name}' was not found on PATH or in Arduino IDE. Install Arduino IDE 2, or set its path in Settings > Languages & Frameworks > Language Servers or settings.toml under languages.arduino.",

src/platform/locales/text/zh.json

@@ -214,7 +214,7 @@
   "JAR Application": "JAR 应用程序",
   "Run an executable JAR": "运行可执行 JAR",
   "Path to JAR": "JAR 路径",
-  "Default (java on PATH)": "默认（PATH 中的 java）",
+  "Default (the project's JDK)": "默认（项目 JDK）",
   "Arduino tool '{configured}' was not found. Set its path in Settings > Languages & Frameworks > Language Servers, or in settings.toml under languages.arduino.": "未找到 Arduino 工具“{configured}”。请在设置 > 语言和框架 > 语言服务器中配置其路径，或在 settings.toml 的 languages.arduino 下配置。",
   "Arduino tool '{name}' was not found on PATH or in Arduino IDE. Install Arduino IDE 2, or set its path in Settings > Languages & Frameworks > Language Servers or settings.toml under languages.arduino.": "在 PATH 或 Arduino IDE 中未找到 Arduino 工具“{name}”。请安装 Arduino IDE 2，或在设置 > 语言和框架 > 语言服务器中配置其路径，也可在 settings.toml 的 languages.arduino 下配置。",
   "Install Arduino IDE 2 (includes Arduino Language Server, Arduino CLI and clangd) and the board's core. Configure the server command and arguments in Settings > Languages & Frameworks > Language Servers, or set languages.arduino.cli, languages.arduino.clangd, languages.arduino.languageServer and languages.arduino.cliConfig in settings.toml. Set the board FQBN in sketch.yaml or languages.arduino.fqbn in settings.toml.": "请安装 Arduino IDE 2（包含 Arduino Language Server、Arduino CLI 和 clangd）及开发板核心。在设置 > 语言和框架 > 语言服务器中配置服务器命令和参数，或在 settings.toml 中设置 languages.arduino.cli、languages.arduino.clangd、languages.arduino.languageServer 和 languages.arduino.cliConfig。在 sketch.yaml 或 settings.toml 的 languages.arduino.fqbn 中设置开发板 FQBN。",