builder

src/main/java/com/github/hcsp/encapsulation/UserBuilder.java

@@ -2,5 +2,48 @@
 
 public class UserBuilder {
     // 请在这里使用builder模式建造User对象
+    private String firstName;
+
+    /**
+     * 用户的姓
+     */
+    private String lastName;
+
+    /**
+     * 用户的电话
+     */
+    private String phoneNumber;
+
+    /**
+     * 用户的地址
+     */
+    private String address;
+
+    public UserBuilder() {
+    }
+
+    public UserBuilder firstName(String firstName) {
+        this.firstName = firstName;
+        return this;
+    }
+
+    public UserBuilder lastName(String lastName) {
+        this.lastName = lastName;
+        return this;
+    }
+
+    public UserBuilder phoneNumber(String phoneNumber) {
+        this.phoneNumber = phoneNumber;
+        return this;
+    }
+
+    public UserBuilder address(String address) {
+        this.address = address;
+        return this;
+    }
+
+    public User build() {
+        return new User(firstName, lastName, phoneNumber, address);
+    }
     // 所需的接口请参阅UserBuilderTest测试类
 }

src/test/java/com/github/hcsp/encapsulation/UserBuilderTest.java

@@ -7,7 +7,7 @@ public class UserBuilderTest {
     @Test
     public void canUseBuilderToCreateObjects() {
         User user =
-                new UserBuilder()
+                new UserBuilder(firstName, lastName, phoneNumber, address)
                         .firstName("德华")
                         .lastName("刘")
                         .phoneNumber("我也不知道")