建造者模式java 代码实例

以下是一个简单的建造者模式 Java 代码实例：

public class Computer {
    private String cpu;
    private String gpu;
    private int memory;
    private int storage;

    public Computer(String cpu, String gpu, int memory, int storage) {
        this.cpu = cpu;
        this.gpu = gpu;
        this.memory = memory;
        this.storage = storage;
    }

    public String getCpu() {
        return cpu;
    }

    public String getGpu() {
        return gpu;
    }

    public int getMemory() {
        return memory;
    }

    public int getStorage() {
        return storage;
    }

    public static class Builder {
        private String cpu;
        private String gpu;
        private int memory;
        private int storage;

        public Builder setCpu(String cpu) {
            this.cpu = cpu;
            return this;
        }

        public Builder setGpu(String gpu) {
            this.gpu = gpu;
            return this;
        }

        public Builder setMemory(int memory) {
            this.memory = memory;
            return this;
        }

        public Builder setStorage(int storage) {
            this.storage = storage;
            return this;
        }

        public Computer build() {
            return new Computer(cpu, gpu, memory, storage);
        }
    }
}

使用建造者模式创建一个 Computer 对象的示例代码：

Computer computer = new Computer.Builder()
        .setCpu("Intel Core i7")
        .setGpu("Nvidia GeForce RTX 3080")
        .setMemory(16)
        .setStorage(512)
        .build();

这个示例中，Computer 类的构造函数是私有的，因此只能通过 Builder 类来创建 Computer 对象。Builder 类提供了一系列 set 方法来设置 Computer 对象的属性，最后调用 build 方法来创建 Computer 对象。这种方式可以避免使用过多的构造函数参数，使代码更加清晰易懂。