style: add generic wildcard

src/main/java/org/apache/ibatis/executor/BaseExecutor.java

@@ -131,7 +131,7 @@ public List<BatchResult> flushStatements(boolean isRollBack) throws SQLException
   }
 
   @Override
-  public <E> List<E> query(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler resultHandler)
+  public <E> List<E> query(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler<?> resultHandler)
       throws SQLException {
     BoundSql boundSql = ms.getBoundSql(parameter);
     CacheKey key = createCacheKey(ms, parameter, rowBounds, boundSql);
@@ -140,7 +140,7 @@ public <E> List<E> query(MappedStatement ms, Object parameter, RowBounds rowBoun
 
   @SuppressWarnings("unchecked")
   @Override
-  public <E> List<E> query(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler resultHandler,
+  public <E> List<E> query(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler<?> resultHandler,
       CacheKey key, BoundSql boundSql) throws SQLException {
     ErrorContext.instance().resource(ms.getResource()).activity("executing a query").object(ms.getId());
     if (closed) {
@@ -286,7 +286,7 @@ public void clearLocalCache() {
   protected abstract List<BatchResult> doFlushStatements(boolean isRollback) throws SQLException;
 
   protected abstract <E> List<E> doQuery(MappedStatement ms, Object parameter, RowBounds rowBounds,
-      ResultHandler resultHandler, BoundSql boundSql) throws SQLException;
+      ResultHandler<?> resultHandler, BoundSql boundSql) throws SQLException;
 
   protected abstract <E> Cursor<E> doQueryCursor(MappedStatement ms, Object parameter, RowBounds rowBounds,
       BoundSql boundSql) throws SQLException;
@@ -337,7 +337,7 @@ private void handleLocallyCachedOutputParameters(MappedStatement ms, CacheKey ke
   }
 
   private <E> List<E> queryFromDatabase(MappedStatement ms, Object parameter, RowBounds rowBounds,
-      ResultHandler resultHandler, CacheKey key, BoundSql boundSql) throws SQLException {
+      ResultHandler<?> resultHandler, CacheKey key, BoundSql boundSql) throws SQLException {
     List<E> list;
     localCache.putObject(key, EXECUTION_PLACEHOLDER);
     try {

src/main/java/org/apache/ibatis/executor/BatchExecutor.java

@@ -81,7 +81,7 @@ public int doUpdate(MappedStatement ms, Object parameterObject) throws SQLExcept
 
   @Override
   public <E> List<E> doQuery(MappedStatement ms, Object parameterObject, RowBounds rowBounds,
-      ResultHandler resultHandler, BoundSql boundSql) throws SQLException {
+      ResultHandler<?> resultHandler, BoundSql boundSql) throws SQLException {
     Statement stmt = null;
     try {
       flushStatements();

src/main/java/org/apache/ibatis/executor/CachingExecutor.java

@@ -83,15 +83,15 @@ public <E> Cursor<E> queryCursor(MappedStatement ms, Object parameter, RowBounds
   }
 
   @Override
-  public <E> List<E> query(MappedStatement ms, Object parameterObject, RowBounds rowBounds, ResultHandler resultHandler)
+  public <E> List<E> query(MappedStatement ms, Object parameterObject, RowBounds rowBounds, ResultHandler<?> resultHandler)
       throws SQLException {
     BoundSql boundSql = ms.getBoundSql(parameterObject);
     CacheKey key = createCacheKey(ms, parameterObject, rowBounds, boundSql);
     return query(ms, parameterObject, rowBounds, resultHandler, key, boundSql);
   }
 
   @Override
-  public <E> List<E> query(MappedStatement ms, Object parameterObject, RowBounds rowBounds, ResultHandler resultHandler,
+  public <E> List<E> query(MappedStatement ms, Object parameterObject, RowBounds rowBounds, ResultHandler<?> resultHandler,
       CacheKey key, BoundSql boundSql) throws SQLException {
     Cache cache = ms.getCache();
     if (cache != null) {

src/main/java/org/apache/ibatis/executor/Executor.java

@@ -32,14 +32,14 @@
  */
 public interface Executor {
 
-  ResultHandler NO_RESULT_HANDLER = null;
+  ResultHandler<?> NO_RESULT_HANDLER = null;
 
   int update(MappedStatement ms, Object parameter) throws SQLException;
 
-  <E> List<E> query(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler resultHandler,
+  <E> List<E> query(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler<?> resultHandler,
       CacheKey cacheKey, BoundSql boundSql) throws SQLException;
 
-  <E> List<E> query(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler resultHandler)
+  <E> List<E> query(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler<?> resultHandler)
       throws SQLException;
 
   <E> Cursor<E> queryCursor(MappedStatement ms, Object parameter, RowBounds rowBounds) throws SQLException;

src/main/java/org/apache/ibatis/executor/ReuseExecutor.java

@@ -53,7 +53,7 @@ public int doUpdate(MappedStatement ms, Object parameter) throws SQLException {
   }
 
   @Override
-  public <E> List<E> doQuery(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler resultHandler,
+  public <E> List<E> doQuery(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler<?> resultHandler,
       BoundSql boundSql) throws SQLException {
     Configuration configuration = ms.getConfiguration();
     StatementHandler handler = configuration.newStatementHandler(wrapper, ms, parameter, rowBounds, resultHandler,

src/main/java/org/apache/ibatis/executor/SimpleExecutor.java

@@ -54,7 +54,7 @@ public int doUpdate(MappedStatement ms, Object parameter) throws SQLException {
   }
 
   @Override
-  public <E> List<E> doQuery(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler resultHandler,
+  public <E> List<E> doQuery(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler<?> resultHandler,
       BoundSql boundSql) throws SQLException {
     Statement stmt = null;
     try {

src/main/java/org/apache/ibatis/executor/loader/ResultLoaderMap.java

@@ -300,7 +300,7 @@ protected List<BatchResult> doFlushStatements(boolean isRollback) throws SQLExce
 
     @Override
     protected <E> List<E> doQuery(MappedStatement ms, Object parameter, RowBounds rowBounds,
-        ResultHandler resultHandler, BoundSql boundSql) throws SQLException {
+        ResultHandler<?> resultHandler, BoundSql boundSql) throws SQLException {
       throw new UnsupportedOperationException("Not supported.");
     }