[EDIT] userIdによる検索機能に日付も入力するように変更しました。

src/main/java/com/example/demo/app/domain/service/TransactionService.java

@@ -10,7 +10,7 @@ public interface TransactionService {
 
 	public Map<LocalDate, List<TransactionModel>> findAllByDate(LocalDate startDate, LocalDate endDate, Long userId);
 	
-	public TransactionModel findByUserId(TransactionModel transactionModel);
+	public List<TransactionModel> findByUserIdAndDate(LocalDate todayDate, Long userId);
 	
 	public int findTotalIncome(LocalDate startDate, LocalDate endDate, Long userId);
 	

src/main/java/com/example/demo/app/domain/service/impl/TransactionServiceImpl.java

@@ -46,15 +46,10 @@ public class TransactionServiceImpl implements TransactionService {
 		
 	}
 
-	public TransactionModel findByUserId(TransactionModel transactionModel) {
+	public List<TransactionModel> findByUserIdAndDate(LocalDate todayDate, Long userId) {
 
-		TransactionEntity transactionEntity = transactionRepository.findByUserId(transactionModel.getUserId());
+		return TransactionModel.convertFrom(transactionRepository.findByUserIdAndDate(todayDate, userId));
 
-		if (transactionEntity == null) {
-			return null;
-		}
-
-		return TransactionModel.convertFrom(transactionEntity);
 	}
 
 }

src/main/java/com/example/demo/app/infra/repository/TransactionRepository.java

@@ -5,14 +5,13 @@ import java.util.List;
 
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.Query;
-import org.springframework.data.repository.query.Param;
 
 import com.example.demo.app.infra.entity.TransactionEntity;
 
 public interface TransactionRepository extends JpaRepository<TransactionEntity, Long> {
 
-	@Query("select t from TransactionEntity t where t.userEntity.userId = :userId")
+	@Query("select t from TransactionEntity t where t.userEntity.userId = :userId and t.transactionDate = :transactionDate")
-	public TransactionEntity findByUserId(@Param("userId") Long userId);
+	public List<TransactionEntity> findByUserIdAndDate(LocalDate todayDate, Long userId);
 
 	@Query("select t from TransactionEntity t where (t.transactionDate between :startDate and :endDate) and (t.userId = :userId) order by t.transactionDate asc")
 	public List<TransactionEntity> findAllByDateAndUserId(LocalDate startDate, LocalDate endDate, Long userId);

src/main/java/com/example/demo/app/presentation/controller/TransactionController.java

@@ -1,8 +1,22 @@
 package com.example.demo.app.presentation.controller;
 
-import org.springframework.stereotype.Controller;
+import java.time.LocalDate;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
 
+import jakarta.servlet.http.HttpSession;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+
+import com.example.demo.app.domain.service.CategoryService;
 import com.example.demo.app.domain.service.TransactionService;
+import com.example.demo.app.presentation.form.CategoryForm;
+import com.example.demo.app.presentation.form.TransactionForm;
 
 import lombok.RequiredArgsConstructor;
 
@@ -11,7 +25,59 @@ import lombok.RequiredArgsConstructor;
 public class TransactionController {
 
 	private final TransactionService transactionService;
+	private final CategoryService categoryService;
+
+	// 一覧画面
+
+	@GetMapping("/transaction/list")
+	public String transactionList(@RequestParam LocalDate startDate, @RequestParam LocalDate endDate, Model model,
+			HttpSession session) {
+
+		LoginUser loginUser = (LoginUser) session.getAttribute("loginUser");
+
+		Map<LocalDate, List<TransactionForm>> transactionFormMap = new HashMap<>();
 		
 		
+		transactionService.findAll(startDate, endDate, loginUser.getUserId).forEach((date, list) -> {
+			List<TransactionForm> transactionFormList = list.stream().map(transaction -> {
+				TransactionForm transactionForm = TransactionForm.convertFrom(
+						transaction,
+						CategoryForm.convertFrom(categoryService.findOne(transaction.getCategoryId())).getCategoryName(),
+						transactionService.findTotalexpense(startDate, endDate, loginUser.getUserId),
+						transactionService.findTotalIncome(startDate, endDate, loginUser.getUserId),
+						CategoryForm.convertFrom(categoryService.findOne(transaction.getCategoryId())).getTransactionType()
+						);
+				return transactionForm;
+			}).collect(Collectors.toList());
+			transactionFormMap.put(date, transactionFormList);
+		});
+
+		model.addAttribute("transactionFormMap", transactionFormMap);
+
+		return "transactionList";
+	}
+
+	// 詳細画面
+	@GetMapping()
+	public String findOne(@RequestParam LocalDate todayDate, Model model, HttpSession session) {
+
+		LoginUser loginUser = (LoginUser) session.getAttribute("loginUser");
+		
+		List<TransactionForm> transactionFormList = transactionService.findByUserIdAndDate(todayDate, ((LoginUser)session.getAttribute("loginUser")).getUserId).stream().map(transaction -> {
+			TransactionForm transactionForm = TransactionForm.convertFrom(
+					transaction,
+					CategoryForm.convertFrom(categoryService.findOne(transaction.getCategoryId())).getCategoryName(),
+					transactionService.findTotalexpense(todayDate, todayDate, loginUser.getUserId),
+					transactionService.findTotalIncome(todayDate, todayDate, loginUser.getUserId),
+					CategoryForm.convertFrom(categoryService.findOne(transaction.getCategoryId())).getTransactionType()
+					);
+			return transactionForm;
+		}).collect(Collectors.toList());
+		
+		
+		model.addAttribute("transactionFormList", transactionFormList);
+
+		return "";
+	}
 
 }