add basic read snippet

Author: morganchen12

firestore/app/src/main/java/com/google/example/firestore/DocSnippets.java

@@ -55,6 +55,7 @@
 import java.util.concurrent.TimeUnit;
 import com.google.firebase.firestore.GeoPoint;
 import com.google.firebase.firestore.Pipeline;
+import com.google.firebase.firestore.PipelineResult;
 import com.google.firebase.firestore.PipelineSource;
 import com.google.firebase.firestore.VectorValue;
 import com.google.firebase.firestore.pipeline.AggregateFunction;
@@ -1586,6 +1587,29 @@ void pipelineConcepts() {
         System.out.println(pipeline);
     }
 
+    void basicPipelineRead() {
+        // [START basic_pipeline_read]
+        Pipeline readDataPipeline = db.pipeline()
+            .collection("users");
+
+        readDataPipeline.execute()
+            .addOnSuccessListener(new OnSuccessListener<Pipeline.Snapshot>() {
+                @Override
+                public void onSuccess(Pipeline.Snapshot snapshot) {
+                    for (PipelineResult result : snapshot.getResults()) {
+                        System.out.println(result.getId() + " => " + result.getData());
+                    }
+                }
+            })
+            .addOnFailureListener(new OnFailureListener() {
+                @Override
+                public void onFailure(@NonNull Exception e) {
+                    System.out.println("Error getting documents: " + e);
+                }
+            });
+        // [END basic_pipeline_read]
+    }
+
     // https://cloud.google.com/firestore/docs/pipeline/overview#initialization
     void pipelineInitialization() {
         // [START pipeline_initialization]

firestore/app/src/main/java/com/google/example/firestore/kotlin/DocSnippets.kt

@@ -1343,6 +1343,24 @@ abstract class DocSnippets(val db: FirebaseFirestore) {
         println(pipeline)
     }
 
+    fun basicPipelineRead() {
+        // [START basic_pipeline_read]
+        val readDataPipeline = db.pipeline()
+            .collection("users")
+
+        // Execute the pipeline and handle the result
+        readDataPipeline.execute()
+            .addOnSuccessListener { result ->
+                for (document in result) {
+                    println("${document.getId()} => ${document.getData()}")
+                }
+            }
+            .addOnFailureListener { exception ->
+                println("Error getting documents: $exception")
+            }
+        // [END basic_pipeline_read]
+    }
+
     // https://cloud.google.com/firestore/docs/pipeline/overview#initialization
     fun pipelineInitialization() {
         // [START pipeline_initialization]