From e3aba219818ee7335e080aac33e03572dd95055c Mon Sep 17 00:00:00 2001
From: Dan Johnson <dan.johnson@sproutsocial.com>
Date: Wed, 13 May 2026 09:57:36 -0500
Subject: [PATCH] feat(highlight): add Java highlighting support

---
 Cargo.lock                           | 11 +++++++++++
 Cargo.toml                           |  1 +
 src/command/diff/highlight/config.rs | 11 +++++++++++
 src/command/diff/highlight/mod.rs    | 17 +++++++++++++++++
 4 files changed, 40 insertions(+)

diff --git a/Cargo.lock b/Cargo.lock
index 7aacde39..d33eafd5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2577,6 +2577,7 @@ dependencies = [
  "tree-sitter-go",
  "tree-sitter-highlight",
  "tree-sitter-html",
+ "tree-sitter-java",
  "tree-sitter-javascript",
  "tree-sitter-json",
  "tree-sitter-md",
@@ -4247,6 +4248,16 @@ dependencies = [
  "tree-sitter-language",
 ]
 
+[[package]]
+name = "tree-sitter-java"
+version = "0.23.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0aa6cbcdc8c679b214e616fd3300da67da0e492e066df01bcf5a5921a71e90d6"
+dependencies = [
+ "cc",
+ "tree-sitter-language",
+]
+
 [[package]]
 name = "tree-sitter-javascript"
 version = "0.23.1"
diff --git a/Cargo.toml b/Cargo.toml
index 3f5e9507..1929d725 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -42,6 +42,7 @@ tree-sitter-md = "0.3"
 tree-sitter-c-sharp = "0.23"
 tree-sitter-ruby = "0.23"
 tree-sitter-elixir = "0.3"
+tree-sitter-java = "0.23"
 once_cell = "1.20"
 arboard = "3.4"
 tui-textarea = "0.7"
diff --git a/src/command/diff/highlight/config.rs b/src/command/diff/highlight/config.rs
index db6b15ae..c46ac334 100644
--- a/src/command/diff/highlight/config.rs
+++ b/src/command/diff/highlight/config.rs
@@ -6,6 +6,9 @@ use super::queries::*;
 // Elixir uses the bundled highlight queries from tree-sitter-elixir
 const ELIXIR_HIGHLIGHTS: &str = tree_sitter_elixir::HIGHLIGHTS_QUERY;
 
+// Java uses the bundled highlight queries from tree-sitter-java
+const JAVA_HIGHLIGHTS: &str = tree_sitter_java::HIGHLIGHTS_QUERY;
+
 pub const HIGHLIGHT_NAMES: &[&str] = &[
     "attribute",
     "comment",
@@ -214,5 +217,13 @@ pub static CONFIGS: Lazy<Vec<(&'static str, LanguageConfig)>> = Lazy::new(|| {
         &mut configs,
     );
 
+    load_config(
+        tree_sitter_java::LANGUAGE.into(),
+        "java",
+        JAVA_HIGHLIGHTS,
+        "java",
+        &mut configs,
+    );
+
     configs
 });
diff --git a/src/command/diff/highlight/mod.rs b/src/command/diff/highlight/mod.rs
index 0a33b05c..97d3e5f6 100644
--- a/src/command/diff/highlight/mod.rs
+++ b/src/command/diff/highlight/mod.rs
@@ -238,6 +238,7 @@ mod tests {
         assert!(extensions.contains(&"json"), "JSON config should be loaded");
         assert!(extensions.contains(&"ex"), "Elixir config should be loaded");
         assert!(extensions.contains(&"exs"), "Elixir script config should be loaded");
+        assert!(extensions.contains(&"java"), "Java config should be loaded");
     }
 
     #[test]
@@ -302,6 +303,22 @@ end
         assert!(has_highlights, "Elixir code should have syntax highlights");
     }
 
+    #[test]
+    fn test_java_highlighting() {
+        let code = r#"package com.example;
+
+public class Hello {
+    public static void main(String[] args) {
+        System.out.println("Hello, Java!");
+    }
+}
+"#;
+        let result = highlight_code(code, "test.java");
+        assert!(!result.is_empty(), "Java highlighting should produce output");
+        let has_highlights = result.iter().any(|(_, h)| h.is_some());
+        assert!(has_highlights, "Java code should have syntax highlights");
+    }
+
     #[test]
     fn test_rust_comment_highlighting() {
         use config::HIGHLIGHT_NAMES;