具有不可变存储的只读字段的类的构造函数

class ImmutableClass {
  constructor(readOnlyField) {
    Object.defineProperty(this, 'readOnlyField', {
      value: readOnlyField,
      writable: false,
      enumerable: true,
      configurable: false
    });
  }
}

const myObject = new ImmutableClass('immutable value');
console.log(myObject.readOnlyField); // 输出：immutable value

// 尝试修改只读字段，将会抛出错误
myObject.readOnlyField = 'modified value'; // TypeError: Cannot assign to read only property 'readOnlyField' of object '#<ImmutableClass>'

public class ImmutableClass {
  private final String readOnlyField;

  public ImmutableClass(String readOnlyField) {
    this.readOnlyField = readOnlyField;
  }

  public String getReadOnlyField() {
    return readOnlyField;
  }
}

ImmutableClass myObject = new ImmutableClass("immutable value");
System.out.println(myObject.getReadOnlyField()); // 输出：immutable value

// 尝试修改只读字段，将会抛出错误
myObject.readOnlyField = "modified value"; // 编译错误：Cannot assign a value to final variable 'readOnlyField'