feat(java-bindings): add java bindings

Cargo.toml

@@ -10,6 +10,8 @@ members = [
     "./plugins/openaddresses-plugin",
     "./plugins/progress-plugin",
     "./plugins/upload-plugin",
+    "./packages/datagen",
+    "crates/datagen-java",
     "./plugins/sql-plugin",
     "./packages/datagen"
 ]

crates/datagen-java/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "datagen-java"
+version = "0.2.0"
+edition = "2021"
+repository = "https://github.com/MarkusJx/datagen"
+license = "MIT"
+
+[lib]
+crate-type = ["cdylib"]
+
+[dependencies]
+serde_json = "1.0.114"
+datagen-rs = { path = "../datagen-rs", features = ["all"] }
+datagen-rs-progress-plugin = { path = "../../plugins/progress-plugin" }
+jni-bindgen = { git = "https://github.com/MarkusJx/jni-bindgen" }
+jni = "0.21.1"
+anyhow = "1.0.80"

crates/datagen-java/src/lib.rs

@@ -0,0 +1,60 @@
+use datagen_rs_progress_plugin::{PluginWithSchemaResult, ProgressPlugin};
+use jni::JNIEnv;
+use jni_bindgen::jni;
+use jni_bindgen::objects::traits::{FromJNI, ObjectFromJNI};
+
+#[jni(package = "com.github.markusjx.datagen.generated")]
+trait GenerateCallback: Send + Sync {
+    fn progress(&self, env: &mut JNIEnv, current: i32, total: i32) -> jni_bindgen::Result<()>;
+}
+
+struct DatagenImpl;
+
+#[jni(
+    package = "com.github.markusjx.datagen.generated",
+    not_null_annotation = "jakarta.validation.constraints.NotNull",
+    nullable_annotation = "jakarta.annotation.Nullable"
+)]
+impl DatagenImpl {
+    #[jni]
+    fn generate_random_data(
+        env: &mut JNIEnv,
+        schema: String,
+        callback: Option<Box<dyn GenerateCallback>>,
+    ) -> anyhow::Result<String> {
+        let vm = env.get_java_vm()?;
+        let schema = serde_json::from_str(&schema)?;
+        let (schema, plugins) = if let Some(callback) = callback {
+            let PluginWithSchemaResult { schema, plugins } =
+                ProgressPlugin::with_schema(schema, move |current, total| {
+                    if let Err(e) =
+                        Self::call_callback(&vm, callback.as_ref(), current as i32, total as i32)
+                    {
+                        eprintln!("Failed to call callback: {}", e);
+                    }
+                })?;
+
+            (schema, Some(plugins))
+        } else {
+            (schema, None)
+        };
+
+        datagen_rs::util::helpers::generate_random_data(schema, plugins)
+    }
+
+    #[jni]
+    fn get_schema() -> anyhow::Result<String> {
+        let schema = datagen_rs::util::helpers::get_schema_value()?;
+        serde_json::to_string_pretty(&schema).map_err(Into::into)
+    }
+
+    fn call_callback(
+        vm: &jni::JavaVM,
+        callback: &dyn GenerateCallback,
+        current: i32,
+        total: i32,
+    ) -> jni_bindgen::Result<()> {
+        let mut env = vm.get_env()?;
+        callback.progress(&mut env, current, total)
+    }
+}