From eeb8fd60d5a17fc774bc73ba541118973f7be414 Mon Sep 17 00:00:00 2001
From: Derek Bailey <derekbailey@google.com>
Date: Tue, 23 Aug 2022 23:17:35 -0700
Subject: [PATCH] Include builder.addOffset for vector of structs (#7470)

---
 src/idl_gen_java.cpp              | 6 +++++-
 tests/MyGame/Example/Monster.java | 9 ++++++---
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/src/idl_gen_java.cpp b/src/idl_gen_java.cpp
index 4dfcf16fb..c6d47ffe8 100644
--- a/src/idl_gen_java.cpp
+++ b/src/idl_gen_java.cpp
@@ -1658,11 +1658,15 @@ class JavaGenerator : public BaseGenerator {
                 field.value.type.struct_def == nullptr
                     ? "builder.add" + GenMethod(field.value.type.VectorType()) +
                           "(" + variable + "[_j]);"
-                    : type_name + ".pack(builder, " + variable + "[_j]);";
+                    : "_unused_offset = " + type_name + ".pack(builder, " +
+                          variable + "[_j]);";
             code += "    int _" + field_name + " = 0;\n";
             code += "    " + element_type_name + "[] " + variable + " = _o." +
                     get_field + "();\n";
             code += "    if (" + variable + " != null) {\n";
+            if (field.value.type.struct_def != nullptr) {
+              code += "      int _unused_offset = 0;\n";
+            }
             code += "      " + namer_.Method("start", field) +
                     "Vector(builder, " + variable + ".length);\n";
             code += "      for (int _j = " + variable +
diff --git a/tests/MyGame/Example/Monster.java b/tests/MyGame/Example/Monster.java
index ff89921ee..b1d5be917 100644
--- a/tests/MyGame/Example/Monster.java
+++ b/tests/MyGame/Example/Monster.java
@@ -549,8 +549,9 @@ public final class Monster extends Table {
     int _test4 = 0;
     MyGame.Example.TestT[] _oTest4 = _o.getTest4();
     if (_oTest4 != null) {
+      int _unused_offset = 0;
       startTest4Vector(builder, _oTest4.length);
-      for (int _j = _oTest4.length - 1; _j >=0; _j--) { MyGame.Example.Test.pack(builder, _oTest4[_j]);}
+      for (int _j = _oTest4.length - 1; _j >=0; _j--) { _unused_offset = MyGame.Example.Test.pack(builder, _oTest4[_j]);}
       _test4 = builder.endVector();
     }
     int _testarrayofstring = 0;
@@ -590,8 +591,9 @@ public final class Monster extends Table {
     int _testarrayofsortedstruct = 0;
     MyGame.Example.AbilityT[] _oTestarrayofsortedstruct = _o.getTestarrayofsortedstruct();
     if (_oTestarrayofsortedstruct != null) {
+      int _unused_offset = 0;
       startTestarrayofsortedstructVector(builder, _oTestarrayofsortedstruct.length);
-      for (int _j = _oTestarrayofsortedstruct.length - 1; _j >=0; _j--) { MyGame.Example.Ability.pack(builder, _oTestarrayofsortedstruct[_j]);}
+      for (int _j = _oTestarrayofsortedstruct.length - 1; _j >=0; _j--) { _unused_offset = MyGame.Example.Ability.pack(builder, _oTestarrayofsortedstruct[_j]);}
       _testarrayofsortedstruct = builder.endVector();
     }
     int _flex = 0;
@@ -604,8 +606,9 @@ public final class Monster extends Table {
     int _test5 = 0;
     MyGame.Example.TestT[] _oTest5 = _o.getTest5();
     if (_oTest5 != null) {
+      int _unused_offset = 0;
       startTest5Vector(builder, _oTest5.length);
-      for (int _j = _oTest5.length - 1; _j >=0; _j--) { MyGame.Example.Test.pack(builder, _oTest5[_j]);}
+      for (int _j = _oTest5.length - 1; _j >=0; _j--) { _unused_offset = MyGame.Example.Test.pack(builder, _oTest5[_j]);}
       _test5 = builder.endVector();
     }
     int _vectorOfLongs = 0;