clippy (#1140)

Author: parthchandra

native/core/src/execution/datafusion/schema_adapter.rs

@@ -120,9 +120,9 @@ impl SchemaAdapter for CometSchemaAdapter {
 
         Ok((
             Arc::new(SchemaMapping {
-                projected_table_schema: self.projected_table_schema.clone(),
+                projected_table_schema: Arc::<Schema>::clone(&self.projected_table_schema),
                 field_mappings,
-                table_schema: self.table_schema.clone(),
+                table_schema: Arc::<Schema>::clone(&self.table_schema),
             }),
             projection,
         ))
@@ -218,7 +218,7 @@ impl SchemaMapper for SchemaMapping {
         // Necessary to handle empty batches
         let options = RecordBatchOptions::new().with_row_count(Some(batch.num_rows()));
 
-        let schema = self.projected_table_schema.clone();
+        let schema = Arc::<Schema>::clone(&self.projected_table_schema);
         let record_batch = RecordBatch::try_new_with_options(schema, cols, &options)?;
         Ok(record_batch)
     }

native/core/src/parquet/mod.rs

@@ -621,8 +621,10 @@ fn get_batch_reader<'a>(handle: jlong) -> Result<&'a mut ParquetRecordBatchReade
     Ok(&mut get_batch_context(handle)?.batch_reader)
 }
 
+/// # Safety
+/// This function is inherently unsafe since it deals with raw pointers passed from JNI.
 #[no_mangle]
-pub extern "system" fn Java_org_apache_comet_parquet_Native_initRecordBatchReader(
+pub unsafe extern "system" fn Java_org_apache_comet_parquet_Native_initRecordBatchReader(
     e: JNIEnv,
     _jclass: JClass,
     file_path: jstring,
@@ -646,62 +648,66 @@ pub extern "system" fn Java_org_apache_comet_parquet_Native_initRecordBatchReade
             .unwrap()
             .with_batch_size(8192); // TODO: (ARROW NATIVE) Use batch size configured in JVM
 
+        let num_row_groups;
+        let mut total_rows: i64 = 0;
         //TODO: (ARROW NATIVE) if we can get the ParquetMetadata serialized, we need not do this.
-        let metadata = builder.metadata().clone();
-
-        let mut columns_to_read: Vec<usize> = Vec::new();
-        let columns_to_read_array = JObjectArray::from_raw(required_columns);
-        let array_len = env.get_array_length(&columns_to_read_array)?;
-        let mut required_columns: Vec<String> = Vec::new();
-        for i in 0..array_len {
-            let p: JString = env
-                .get_object_array_element(&columns_to_read_array, i)?
-                .into();
-            required_columns.push(env.get_string(&p)?.into());
-        }
-        for (i, col) in metadata
-            .file_metadata()
-            .schema_descr()
-            .columns()
-            .iter()
-            .enumerate()
         {
-            for (_, required) in required_columns.iter().enumerate() {
-                if col.name().to_uppercase().eq(&required.to_uppercase()) {
-                    columns_to_read.push(i);
-                    break;
+            let metadata = builder.metadata();
+
+            let mut columns_to_read: Vec<usize> = Vec::new();
+            let columns_to_read_array = JObjectArray::from_raw(required_columns);
+            let array_len = env.get_array_length(&columns_to_read_array)?;
+            let mut required_columns: Vec<String> = Vec::new();
+            for i in 0..array_len {
+                let p: JString = env
+                    .get_object_array_element(&columns_to_read_array, i)?
+                    .into();
+                required_columns.push(env.get_string(&p)?.into());
+            }
+            for (i, col) in metadata
+                .file_metadata()
+                .schema_descr()
+                .columns()
+                .iter()
+                .enumerate()
+            {
+                for required in required_columns.iter() {
+                    if col.name().to_uppercase().eq(&required.to_uppercase()) {
+                        columns_to_read.push(i);
+                        break;
+                    }
                 }
             }
-        }
-        //TODO: (ARROW NATIVE) make this work for complex types (especially deeply nested structs)
-        let mask = ProjectionMask::leaves(metadata.file_metadata().schema_descr(), columns_to_read);
-        // Set projection mask to read only root columns 1 and 2.
-        builder = builder.with_projection(mask);
-
-        let mut row_groups_to_read: Vec<usize> = Vec::new();
-        let mut total_rows: i64 = 0;
-        // get row groups -
-        for (i, rg) in metadata.row_groups().into_iter().enumerate() {
-            let rg_start = rg.file_offset().unwrap();
-            let rg_end = rg_start + rg.compressed_size();
-            if rg_start >= start && rg_end <= start + length {
-                row_groups_to_read.push(i);
-                total_rows += rg.num_rows();
+            //TODO: (ARROW NATIVE) make this work for complex types (especially deeply nested structs)
+            let mask =
+                ProjectionMask::leaves(metadata.file_metadata().schema_descr(), columns_to_read);
+            // Set projection mask to read only root columns 1 and 2.
+
+            let mut row_groups_to_read: Vec<usize> = Vec::new();
+            // get row groups -
+            for (i, rg) in metadata.row_groups().iter().enumerate() {
+                let rg_start = rg.file_offset().unwrap();
+                let rg_end = rg_start + rg.compressed_size();
+                if rg_start >= start && rg_end <= start + length {
+                    row_groups_to_read.push(i);
+                    total_rows += rg.num_rows();
+                }
             }
+            num_row_groups = row_groups_to_read.len();
+            builder = builder
+                .with_projection(mask)
+                .with_row_groups(row_groups_to_read.clone())
         }
 
         // Build a sync parquet reader.
-        let batch_reader = builder
-            .with_row_groups(row_groups_to_read.clone())
-            .build()
-            .unwrap();
+        let batch_reader = builder.build().unwrap();
 
         let ctx = BatchContext {
             batch_reader,
             current_batch: None,
             reader_state: ParquetReaderState::Init,
-            num_row_groups: row_groups_to_read.len() as i32,
-            total_rows: total_rows,
+            num_row_groups: num_row_groups as i32,
+            total_rows,
         };
         let res = Box::new(ctx);
         Ok(Box::into_raw(res) as i64)