feat: adjust panic to Java Exception

prql-java/java/pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>org.prqllang</groupId>
     <artifactId>prql-java</artifactId>
-    <version>0.2.1</version>
+    <version>0.5.2</version>
 
     <name>${project.groupId}:${project.artifactId}</name>
     <description>prql-compiler api for java</description>

prql-java/java/src/main/java/org/prql/prql4j/PrqlCompiler.java

@@ -3,8 +3,9 @@
 import java.io.IOException;
 
 public class PrqlCompiler {
-    public static native String toSql(String query);
-    public static native String toJson(String query);
+    public static native String toSql(String query) throws Exception;
+    public static native String toJson(String query) throws Exception;
+    public static native String format(String query) throws Exception;
 
     static {
         try {

prql-java/java/src/test/java/org/prql/prql4j/PrqlCompilerTest.java

@@ -4,7 +4,7 @@
 
 public class PrqlCompilerTest {
     @Test
-    public void compile() {
+    public void compile() throws Exception {
         String found = PrqlCompiler.toSql("from table");
 
         // remove signature
@@ -16,4 +16,9 @@ public void compile() {
                 "  table";
         assert expected.equalsIgnoreCase(found);
     }
+
+    @Test(expected = Exception.class)
+    public void compileWithError() throws Exception {
+       PrqlCompiler.toSql("from table | filter id >> 1");
+    }
 }

prql-java/src/lib.rs

@@ -1,7 +1,7 @@
 use jni::objects::{JClass, JString};
 use jni::sys::jstring;
 use jni::JNIEnv;
-use prql_compiler::{json, prql_to_pl, Options};
+use prql_compiler::{json, prql_to_pl, pl_to_prql, Options, ErrorMessages};
 
 #[no_mangle]
 #[allow(non_snake_case)]
@@ -14,11 +14,23 @@ pub extern "system" fn Java_org_prql_prql4j_PrqlCompiler_toSql(
         .get_string(query)
         .expect("Couldn't get java string!")
         .into();
-    let rs_sql_str: String = prql_compiler::compile(&prql_query, &Options::default())
-        .expect("Couldn't compile query to prql!");
-    env.new_string(rs_sql_str)
-        .expect("Couldn't create java string!")
-        .into_raw()
+    let result = prql_compiler::compile(&prql_query, &Options::default());
+    java_string_with_exception(result, &env)
+}
+
+#[no_mangle]
+#[allow(non_snake_case)]
+pub extern "system" fn Java_org_prql_prql4j_PrqlCompiler_format(
+    env: JNIEnv,
+    _class: JClass,
+    query: JString,
+) -> jstring {
+    let prql_query: String = env
+        .get_string(query)
+        .expect("Couldn't get java string!")
+        .into();
+    let result = prql_to_pl(&prql_query).and_then(pl_to_prql);
+    java_string_with_exception(result,&env)
 }
 
 #[no_mangle]
@@ -32,9 +44,20 @@ pub extern "system" fn Java_org_prql_prql4j_PrqlCompiler_toJson(
         .get_string(query)
         .expect("Couldn't get java string!")
         .into();
-    let rs_json_str: String = { prql_to_pl(&prql_query).and_then(json::from_pl) }
-        .expect("Couldn't get json from prql query!");
-    env.new_string(rs_json_str)
-        .expect("Couldn't create java string!")
-        .into_raw()
+    let result = prql_to_pl(&prql_query).and_then(json::from_pl);
+    return java_string_with_exception(result, &env);
+}
+
+fn java_string_with_exception(result: Result<String, ErrorMessages>, env: &JNIEnv) -> jstring {
+    if result.is_ok() {
+        env.new_string(result.unwrap())
+            .expect("Couldn't create java string!")
+            .into_raw()
+    } else {
+        let exception = env.find_class("java/lang/Exception").unwrap();
+        if let Err(e) = env.throw_new(exception, result.err().unwrap().to_string()) {
+            println!("Error throwing exception: {:?}", e);
+        }
+        std::ptr::null_mut() as jstring
+    }
 }