Implement FileDataModel.java

src/data/FileDataModel.java

@@ -1,46 +1,98 @@
 package data;
 
+import java.io.FileWriter;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.ArrayList;
 import java.util.List;
+
 import model.*;
+import jsonlib.types.JSONObject;
+import jsonlib.types.JSONList;
+import jsonlib.types.JSONDict;
+import jsonlib.JSONSerializableFactory;
+import jsonlib.JSONParser;
+import jsonlib.JSONExpectFailedException;
 
 public class FileDataModel {
-  public void loadBooks(String filePath) {
-    // TODO: Implement method 'filePath'.
-    throw new UnsupportedOperationException("Unimplemented method 'filePath'");
+  private static final String BOOKS_FILEPATH = "books.json";
+  private static final String STUDENTS_FILEPATH = "students.json";
+  private static final String CATEGORIES_FILEPATH = "categories.json";
+  private static final String LOANS_FILEPATH = "loans.json";
+
+  public List<Book> loadBooks() {
+    return loadFromFile(BOOKS_FILEPATH);
+  }
+
+  public List<Student> loadStudents() {
+    return loadFromFile(STUDENTS_FILEPATH);
   }
 
-  public void saveBooks(List<Book> books, String filePath) {
-    // TODO: Implement method 'saveBooks'.
-    throw new UnsupportedOperationException("Unimplemented method 'saveBooks'");
+  public List<Category> loadCategories() {
+    return loadFromFile(CATEGORIES_FILEPATH);
   }
 
-  public void loadStudents(String filePath) {
-    // TODO: Implement method 'loadStudents'.
-    throw new UnsupportedOperationException("Unimplemented method 'loadStudents'");
+  public List<Loan> loadLoans() {
+    return loadFromFile(LOANS_FILEPATH);
   }
 
-  public void saveStudents(List<Student> students, String filePath) {
-    // TODO: Implement method 'saveStudents'.
-    throw new UnsupportedOperationException("Unimplemented method 'saveStudents'");
+  public void saveBooks(List<Book> books) {
+    writeToFile(BOOKS_FILEPATH, JSONObject.fromList(books).toString());
   }
 
-  public void loadCategories(String filePath) {
-    // TODO: Implement method 'loadCategories'.
-    throw new UnsupportedOperationException("Unimplemented method 'loadCategories'");
+  public void saveStudents(List<Student> students) {
+    writeToFile(STUDENTS_FILEPATH, JSONObject.fromList(students).toString());
   }
 
-  public void saveCategories(List<Category> categories, String filePath) {
-    // TODO: Implement method 'saveCategories'.
-    throw new UnsupportedOperationException("Unimplemented method 'saveCategories'");
+  public void saveCategories(List<Category> categories) {
+    writeToFile(CATEGORIES_FILEPATH, JSONObject.fromList(categories).toString());
   }
 
-  public void loadLoans(String filePath) {
-    // TODO: Implement method 'loadLoans'.
-    throw new UnsupportedOperationException("Unimplemented method 'loadLoans'");
+  public void saveLoans(List<Loan> loans) {
+    writeToFile(LOANS_FILEPATH, JSONObject.fromList(loans).toString());
   }
 
-  public void saveLoans(List<Loan> loans, String filePath) {
-    // TODO: Implement method 'saveLoans'.
-    throw new UnsupportedOperationException("Unimplemented method 'saveLoans'");
+  public void writeToFile(String filePath, String data) {
+    try (FileWriter writer = new FileWriter(filePath)) {
+      writer.write(data);
+    } catch (IOException e) {
+      e.printStackTrace();
+    }
   }
+
+  public String readFromFile(String filePath) {
+    String content = new String();
+    try {
+      content = String.join("\n", Files.readAllLines(Paths.get(filePath)));
+    } catch (IOException e) {
+      e.printStackTrace();
+    }
+
+    return content;
+  }
+
+  public <T> List<T> loadFromFile(String filePath) {
+    String content = readFromFile(filePath);
+    JSONParser parser = new JSONParser(content);
+
+    JSONObject jsonObj = null;
+
+    try {
+      jsonObj = parser.parse();
+    } catch (JSONExpectFailedException e) {
+      e.printStackTrace();
+    }
+
+    List<T> result = new ArrayList<>();
+    JSONList listJSON = (JSONList) jsonObj;
+
+    for (JSONObject itemJSON : listJSON) {
+      T item = (T) JSONSerializableFactory.deserialize((JSONDict) itemJSON);
+      result.add(item);
+    }
+
+    return result;
+  }
+
 }

src/jsonlib/JSONExpectFailedException.java

@@ -0,0 +1,8 @@
+package jsonlib;
+
+public class JSONExpectFailedException extends Exception {
+
+  public JSONExpectFailedException(String msg) {
+    super(msg);
+  }
+}

src/jsonlib/JSONParser.java

@@ -1,5 +1,6 @@
 package jsonlib;
 
+import jsonlib.types.JSONBoolean;
 import jsonlib.types.JSONDict;
 import jsonlib.types.JSONList;
 import jsonlib.types.JSONNumber;
@@ -80,7 +81,7 @@ private JSONNumber parseNumber() throws JSONExpectFailedException {
     StringBuilder integerPartStr = new StringBuilder();
     StringBuilder floatingPartStr = new StringBuilder();
     boolean isFloat = false;
-    
+
     while (peek() != '\0' && Character.isDigit(peek()))
       integerPartStr.append(consume());
 
@@ -101,8 +102,13 @@ private JSONNumber parseNumber() throws JSONExpectFailedException {
       double number = Double.valueOf(integerPartStr + "." + floatingPartStr);
       return new JSONNumber<Double>(sign * number);
     } else {
-      int number = Integer.valueOf(integerPartStr.toString());
-      return new JSONNumber<Integer>(sign * number);
+      try {
+        int number = Integer.valueOf(integerPartStr.toString());
+        return new JSONNumber<Integer>(sign * number);
+      } catch (NumberFormatException e) {
+        long number = Long.valueOf(integerPartStr.toString());
+        return new JSONNumber<Long>(sign * number);
+      }
     }
   }
 
@@ -146,6 +152,16 @@ private JSONDict parseDict() throws JSONExpectFailedException {
     return dict;
   }
 
+  private JSONBoolean parseBoolean() throws JSONExpectFailedException {
+    if (peek() == 't') {
+      expect("true");
+      return new JSONBoolean(true);
+    } else {
+      expect("false");
+      return new JSONBoolean(false);
+    }
+  }
+
   public JSONObject parse() throws JSONExpectFailedException {
     while (peek() != '\0') {
       switch (peek()) {
@@ -160,22 +176,15 @@ public JSONObject parse() throws JSONExpectFailedException {
             return parseNumber();
           else if (Character.isWhitespace(peek()))
             consume();
+          else if (peek() == 't' || peek() == 'f')
+            return parseBoolean();
           else
             // TODO: handle invalid characters properly.
             throw new UnsupportedOperationException("not implemented yet");
-
-          // TODO: handle json boolean and null
           break;
       }
     }
     return null;
   }
 
 }
-
-class JSONExpectFailedException extends Exception {
-
-  public JSONExpectFailedException(String msg) {
-    super(msg);
-  }
-}

src/jsonlib/types/JSONBoolean.java

@@ -0,0 +1,36 @@
+package jsonlib.types;
+
+public class JSONBoolean extends JSONObject {
+  private boolean value;
+
+  public JSONBoolean(boolean value) {
+    this.value = value;
+  }
+
+  public boolean getValue() {
+    return this.value;
+  }
+
+  @Override
+  public String toString() {
+    return value ? "true" : "false";
+  }
+
+  @Override
+  public int hashCode() {
+    return this.value ? 1 : 0;
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (obj == null)
+      return false;
+
+    if (!(obj instanceof JSONBoolean))
+      return false;
+
+    JSONBoolean other = (JSONBoolean) obj;
+
+    return this.value == other.value;
+  }
+}

src/jsonlib/types/JSONDict.java

@@ -53,6 +53,14 @@ public int getInteger(String key) {
     return jsonNumber.getValue();
   }
 
+  public boolean getBoolean(String key) {
+    JSONObject obj = this.get(key);
+    if (!(obj instanceof JSONBoolean))
+      throw new IllegalArgumentException(String.format("dict[%s] is not a boolean", key));
+
+    return ((JSONBoolean) obj).getValue();
+  }
+
   @Override
   public String toString() {
     StringBuilder sb = new StringBuilder();

src/jsonlib/types/JSONObject.java

@@ -22,6 +22,10 @@ public static <T extends JSONSerializable> JSONObject fromDict(Map<String, T> da
     return new JSONDict(data);
   }
 
+  public static JSONObject fromBoolean(boolean data) {
+    return new JSONBoolean(data);
+  }
+
   @Override
   public abstract String toString();
 }

src/model/Book.java

@@ -1,32 +1,71 @@
 package model;
 
-public class Book {
+import jsonlib.JSONSerializable;
+import jsonlib.types.JSONObject;
+import jsonlib.types.JSONDict;
+
+public class Book implements JSONSerializable {
   private String title;
   private String author;
   private String isbn;
   private int publicationYear;
   private boolean isBorrowed;
 
-
-//Constructor
-  public Book(String title,String author,String isbn,int publicationYear,boolean isBorrowed){
-      this.title=title;
-      this.author=author;
-      this.isbn=isbn;this.publicationYear=publicationYear;
-      this.isBorrowed=isBorrowed;
+  // Constructor
+  public Book(String title, String author, String isbn, int publicationYear, boolean isBorrowed) {
+    this.title = title;
+    this.author = author;
+    this.isbn = isbn;
+    this.publicationYear = publicationYear;
+    this.isBorrowed = isBorrowed;
   }
-//Setter
+
+  // Setter
   public void borrowBook() {
-      this.isBorrowed=true;
+    this.isBorrowed = true;
   }
 
   public void returnBook() {
-      this.isBorrowed=false;
-  }
-//Getter
-  public String  getTitle()           {return this.title;}
-  public String  getAuthor()          {return this.author;}
-  public String  getIsbn()            {return this.isbn;}
-  public Integer getPublicationYear() {return this.publicationYear;}
-  public boolean getIsBorrowed()      {return this.isBorrowed;}
+    this.isBorrowed = false;
+  }
+
+  // Getter
+  public String getTitle() {
+    return this.title;
+  }
+
+  public String getAuthor() {
+    return this.author;
+  }
+
+  public String getIsbn() {
+    return this.isbn;
+  }
+
+  public Integer getPublicationYear() {
+    return this.publicationYear;
+  }
+
+  public boolean getIsBorrowed() {
+    return this.isBorrowed;
+  }
+
+  @Override
+  public JSONObject serialize() {
+    JSONDict result = new JSONDict();
+
+    result.put("class", JSONObject.fromString("Book"));
+    result.put("title", JSONObject.fromString(title));
+    result.put("author", JSONObject.fromString(author));
+    result.put("isbn", JSONObject.fromString(isbn));
+    result.put("publicationYear", JSONObject.fromNumber(publicationYear));
+    result.put("isBorrowed", JSONObject.fromBoolean(isBorrowed));
+
+    return result;
+  }
+
+  public static Book deserialize(JSONDict json) {
+    return new Book(json.getString("title"), json.getString("author"), json.getString("isbn"),
+        json.getInteger("publicationYear"), json.getBoolean("isBorrowed"));
+  }
 }