添加W3

W3/Car.java

@@ -0,0 +1,96 @@
+public class Car {
+    // 1. 私有成员变量（封装核心：隐藏内部数据）
+    private String brand;    // 品牌
+    private String model;    // 型号
+    private int year;        // 生产年份
+    private double price;    // 价格
+
+    // 2. 无参构造方法（构造方法重载 1）
+    public Car() {
+        // 默认值
+        this.brand = "未知品牌";
+        this.model = "未知型号";
+        this.year = 2020;
+        this.price = 0.0;
+    }
+
+    // 3. 带参构造方法（构造方法重载 2：只传入品牌和型号）
+    public Car(String brand, String model) {
+        this.brand = brand;
+        this.model = model;
+        this.year = 2020;  // 默认年份
+        this.price = 0.0;  // 默认价格
+    }
+
+    // 4. 全参构造方法（构造方法重载 3：传入所有属性，含数据校验）
+    public Car(String brand, String model, int year, double price) {
+        this.brand = brand;
+        this.model = model;
+        // 数据校验：年份必须在 1900~2026 之间
+        if (year >= 1900 && year <= 2026) {
+            this.year = year;
+        } else {
+            System.out.println("年份输入不合法，已设置为默认值 2020");
+            this.year = 2020;
+        }
+        // 数据校验：价格不能为负数
+        if (price >= 0) {
+            this.price = price;
+        } else {
+            System.out.println("价格输入不合法，已设置为默认值 0.0");
+            this.price = 0.0;
+        }
+    }
+
+    // 5. 公共 getter/setter 方法（封装核心：提供受控访问）
+    public String getBrand() {
+        return brand;
+    }
+
+    public void setBrand(String brand) {
+        this.brand = brand;
+    }
+
+    public String getModel() {
+        return model;
+    }
+
+    public void setModel(String model) {
+        this.model = model;
+    }
+
+    public int getYear() {
+        return year;
+    }
+
+    public void setYear(int year) {
+        // 校验年份
+        if (year >= 1900 && year <= 2026) {
+            this.year = year;
+        } else {
+            System.out.println("年份输入不合法，未修改");
+        }
+    }
+
+    public double getPrice() {
+        return price;
+    }
+
+    public void setPrice(double price) {
+        // 校验价格
+        if (price >= 0) {
+            this.price = price;
+        } else {
+            System.out.println("价格输入不合法，未修改");
+        }
+    }
+
+    // 6. 显示车辆信息的方法
+    public void showInfo() {
+        System.out.println("=== 车辆信息 ===");
+        System.out.println("品牌：" + this.brand);
+        System.out.println("型号：" + this.model);
+        System.out.println("生产年份：" + this.year);
+        System.out.println("价格：" + this.price + " 万");
+    }
+}

W3/Main.java

@@ -1,169 +1,25 @@
-import org.jfree.chart.ChartFactory;
-import org.jfree.chart.ChartUtils;
-import org.jfree.chart.JFreeChart;
-import org.jfree.data.category.DefaultCategoryDataset;
-import org.jfree.data.general.DefaultPieDataset;
-
-import java.io.File;
-import java.io.FileWriter;
-import java.io.IOException;
-import java.util.*;
-import java.util.stream.Collectors;
-
 public class Main {
     public static void main(String[] args) {
-        try {
+        // 测试 1：无参构造
-            // 1. 爬取电影数据
+        Car car1 = new Car();
-            MovieCrawler crawler = new MovieCrawler();
+        car1.showInfo();
-            List<Movie> movies = crawler.crawlTopMovies(50); // 爬取50部电影
-            
-            // 2. 数据清洗
-            List<Movie> cleanedMovies = cleanData(movies);
-            
-            // 3. 数据存储
-            saveToCSV(cleanedMovies, "movies.csv");
-            
-            // 4. 数据分析
-            analyzeData(cleanedMovies);
-            
-            // 5. 结果展示
-            displayResults(cleanedMovies);
-            generateCharts(cleanedMovies);
-            
-            System.out.println("爬取完成！共获取了 " + cleanedMovies.size() + " 部电影数据。");
-        } catch (Exception e) {
-            e.printStackTrace();
-        }
-    }
-
-    private static List<Movie> cleanData(List<Movie> movies) {
-        return movies.stream()
-                .map(movie -> {
-                    // 去空格
-                    movie.setTitle(movie.getTitle().trim());
-                    movie.setGenre(movie.getGenre().trim());
-                    movie.setDirector(movie.getDirector().trim());
-                    movie.setActors(movie.getActors().trim());
-                    movie.setSynopsis(movie.getSynopsis().trim());
-                    return movie;
-                })
-                .collect(Collectors.toList());
-    }
-
-    private static void saveToCSV(List<Movie> movies, String fileName) throws IOException {
-        try (FileWriter writer = new FileWriter(fileName)) {
-            // 写入表头
-            writer.write("Title,Year,Rating,Genre,Director,Actors,Synopsis\n");
-            
-            // 写入数据
-            for (Movie movie : movies) {
-                writer.write(String.format("%s,%d,%.1f,%s,%s,%s,%s\n",
-                        escapeCSV(movie.getTitle()),
-                        movie.getYear(),
-                        movie.getRating(),
-                        escapeCSV(movie.getGenre()),
-                        escapeCSV(movie.getDirector()),
-                        escapeCSV(movie.getActors()),
-                        escapeCSV(movie.getSynopsis())));
-            }
-        }
-    }
-
-    private static String escapeCSV(String value) {
-        if (value == null) return "";
-        if (value.contains(",") || value.contains("\n") || value.contains("\"")) {
-            value = value.replace("\"", "\"\"");
-            return "\"" + value + "\"";
-        }
-        return value;
-    }
 
-    private static void analyzeData(List<Movie> movies) {
+        // 测试 2：带参构造（品牌+型号）
-        System.out.println("\n=== 数据分析结果 ===");
+        Car car2 = new Car("Toyota", "Camry");
-        
+        car2.showInfo();
-        // 1. 评分分布
-        System.out.println("\n1. 评分分布：");
-        Map<Double, Long> ratingDistribution = movies.stream()
-                .collect(Collectors.groupingBy(Movie::getRating, Collectors.counting()));
-        ratingDistribution.entrySet().stream()
-                .sorted(Map.Entry.comparingByKey())
-                .forEach(entry -> System.out.printf("评分 %.1f: %d 部\n", entry.getKey(), entry.getValue()));
-        
-        // 2. 年份分布
-        System.out.println("\n2. 年份分布：");
-        Map<Integer, Long> yearDistribution = movies.stream()
-                .collect(Collectors.groupingBy(Movie::getYear, Collectors.counting()));
-        yearDistribution.entrySet().stream()
-                .sorted(Map.Entry.comparingByKey())
-                .forEach(entry -> System.out.printf("年份 %d: %d 部\n", entry.getKey(), entry.getValue()));
-        
-        // 3. 导演作品数排行
-        System.out.println("\n3. 导演作品数排行：");
-        Map<String, Long> directorCount = movies.stream()
-                .collect(Collectors.groupingBy(Movie::getDirector, Collectors.counting()));
-        directorCount.entrySet().stream()
-                .sorted(Map.Entry.<String, Long>comparingByValue().reversed())
-                .limit(10)
-                .forEach(entry -> System.out.printf("%s: %d 部\n", entry.getKey(), entry.getValue()));
-        
-        // 4. 平均评分
-        double averageRating = movies.stream()
-                .mapToDouble(Movie::getRating)
-                .average()
-                .orElse(0);
-        System.out.printf("\n4. 平均评分：%.2f\n", averageRating);
-    }
 
-    private static void displayResults(List<Movie> movies) {
+        // 测试 3：全参构造（合法数据）
-        System.out.println("\n=== 电影数据列表 ===");
+        Car car3 = new Car("Tesla", "Model 3", 2024, 28.9);
-        System.out.printf("%-50s %-10s %-10s %-30s %-30s\n", "Title", "Year", "Rating", "Genre", "Director");
+        car3.showInfo();
-        System.out.println("-------------------------------------------------------------------------------------------------------------------------------");
-        
-        for (Movie movie : movies) {
-            System.out.printf("%-50s %-10d %-10.1f %-30s %-30s\n", 
-                    truncate(movie.getTitle(), 50),
-                    movie.getYear(),
-                    movie.getRating(),
-                    truncate(movie.getGenre(), 30),
-                    truncate(movie.getDirector(), 30));
-        }
-    }
 
-    private static String truncate(String text, int maxLength) {
+        // 测试 4：全参构造（非法数据，触发校验）
-        return text.length() > maxLength ? text.substring(0, maxLength - 3) + "..." : text;
+        Car car4 = new Car("BYD", "Han", 1899, -20.0);
-    }
+        car4.showInfo();
 
-    private static void generateCharts(List<Movie> movies) throws IOException {
+        // 测试 5：通过 setter 修改并校验
-        // 1. 评分分布饼图
+        car4.setYear(2025);
-        DefaultPieDataset ratingDataset = new DefaultPieDataset();
+        car4.setPrice(25.9);
-        Map<Double, Long> ratingDistribution = movies.stream()
+        System.out.println("修改后：");
-                .collect(Collectors.groupingBy(Movie::getRating, Collectors.counting()));
+        car4.showInfo();
-        ratingDistribution.forEach((rating, count) -> ratingDataset.setValue(String.valueOf(rating), count));
-        
-        JFreeChart ratingChart = ChartFactory.createPieChart(
-                "电影评分分布",
-                ratingDataset,
-                true,
-                true,
-                false
-        );
-        ChartUtils.saveChartAsPNG(new File("rating_distribution.png"), ratingChart, 800, 600);
-        
-        // 2. 年份与评分关系图
-        DefaultCategoryDataset yearRatingDataset = new DefaultCategoryDataset();
-        Map<Integer, Double> yearAverageRating = movies.stream()
-                .collect(Collectors.groupingBy(Movie::getYear,
-                        Collectors.averagingDouble(Movie::getRating)));
-        yearAverageRating.forEach((year, avgRating) -> yearRatingDataset.addValue(avgRating, "评分", String.valueOf(year)));
-        
-        JFreeChart yearRatingChart = ChartFactory.createBarChart(
-                "年份与平均评分关系",
-                "年份",
-                "平均评分",
-                yearRatingDataset
-        );
-        ChartUtils.saveChartAsPNG(new File("year_rating_relation.png"), yearRatingChart, 800, 600);
-        
-        System.out.println("\n图表已生成：rating_distribution.png 和 year_rating_relation.png");
     }
-}
+}