1 files changed, 151 insertions, 0 deletions
diff --git a/ufund-api/src/main/java/com/ufund/api/ufundapi/persistence/UserFileDAO.java b/ufund-api/src/main/java/com/ufund/api/ufundapi/persistence/UserFileDAO.java
new file mode 100644
index 0000000..18eec18
--- /dev/null
+++ b/ufund-api/src/main/java/com/ufund/api/ufundapi/persistence/UserFileDAO.java
@@ -0,0 +1,151 @@
+package com.ufund.api.ufundapi.persistence;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.Map;
+import java.util.TreeMap;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.ufund.api.ufundapi.model.User;
+
+@Component
+public class UserFileDAO implements UserDAO {
+
+    private final Map<String, User> users; // cache
+    private final ObjectMapper objectMapper;
+    private final String filename;
+
+    public UserFileDAO(@Value("${users.file}") String filename, ObjectMapper objectMapper) throws IOException {
+        this.filename = filename;
+        this.objectMapper = objectMapper;
+        users = new TreeMap<>();
+        load(); // load the users from the file
+    }
+
+    /**
+     * Load changes from the json file
+     *
+     * @throws IOException Any IO issue with the file
+     */
+    private void load() throws IOException {
+        users.clear();
+
+        User[] usersArray = objectMapper.readValue(new File(filename), User[].class);
+
+        for (User user : usersArray) {
+            users.put(user.getName(), user);
+        }
+    }
+
+    /**
+     * Saves the needs to json
+     *
+     * @return True if the save was successful, false otherwise
+     * @throws IOException If there was an IO issue saving the file
+     */
+    private boolean save() throws IOException {
+        User[] userArray = getUserArray();
+
+        objectMapper.writeValue(new File(filename), userArray);
+        return true;
+    }
+
+    /**
+     * Return an array of the needs
+     *
+     * @return An array of all the needs
+     */
+    private User[] getUserArray() {
+        return users.values().toArray(User[]::new);
+    }
+
+    @Override
+    public User[] getUsers() throws IOException {
+        synchronized (users) {
+            return getUserArray();
+        }
+    }
+
+    /**
+     * Return the user with the String name name or null otherwise
+     * 
+     * @param name Name of desired user
+     * 
+     * @return Desired user, null otherwise
+     * @throws IOException If there was an IO issue saving the file
+     */
+    @Override
+    public User getUser(String name) throws IOException {
+        synchronized (users) {
+            return users.getOrDefault(name, null);
+        }
+    }
+
+    /**
+     * Create a User user
+     * 
+     * @param user User to create
+     * 
+     * @return Desired created user
+     * @throws IOException If there was an IO issue saving the file
+     */
+    @Override
+    public User createUser(User user) throws IOException {
+        synchronized (users) {
+            if (getUser(user.getName()) == null) {
+                User newUser = new User(user);
+                users.put(newUser.getName(), newUser);
+                save();
+                return newUser;
+            } else {
+                return null;
+            }
+        }
+    }
+
+    /**
+     * Update a user that matches the supplied name
+     * 
+     * @param name    The name of the user
+     * @param newUser New user data
+     * 
+     * @return Desired user, null otherwise
+     * @throws IOException If there was an IO issue saving the file
+     */
+    @Override
+    public User updateUser(User newUser, String name) throws IOException {
+        synchronized (users) {
+            if (users.containsKey(name)) {
+                users.put(name, newUser);
+                save();
+                return newUser;
+            } else {
+                return null;
+            }
+        }
+    }
+
+    /**
+     * Delete a user matching the name
+     * 
+     * @param name The name of the user
+     * 
+     * @return True if deleted, false otherwise
+     * @throws IOException If there was an IO issue saving the file
+     */
+    @Override
+    public boolean deleteUser(String name) throws IOException {
+        synchronized (users) {
+            if (users.containsKey(name)) {
+                users.remove(name);
+                return save();
+            } else {
+                return false;
+            }
+        }
+    }
+
+}
+\ No newline at end of file