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如何使用Builder方式创建一个对象？针对这个问题，这篇文章详细介绍了相对应的分析和解答，希望可以帮助更多想解决这个问题的小伙伴找到更简单易行的方法。
创建Person类
public class Person {
private String name;
private int age;
private float height;
private float weight;
public Person(String name, int age, float height, float weight) {
this.name = name;
this.age = age;
this.height = height;
this.weight = weight;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public float getHeight() {
return height;
}
public void setHeight(float height) {
this.height = height;
}
public float getWeight() {
return weight;
}
public void setWeight(float weight) {
this.weight = weight;
}
}那么创建对象就是这样，后面参数不容易看出表示的是什么，可读性不强
new Person("冯提莫",18,150,43);
new Person("温婉",17,164,48);用Builder模式进行改造
创建一个Builder类，属性和Person类一样，加上SetXxx()方法
static class Builder{
private String name;
private int age;
private float height;
private float weight;
public void setName(String name) {
this.name = name;
}
public void setAge(int age) {
this.age = age;
}
public void setHeight(float height) {
this.height = height;
}
public void setWeight(float weight) {
this.weight = weight;
}
}将Person的构造方法改为传入Builder对象，将Builder对象的属性值都赋予Person对象
public Person(Builder builder){
this.name = builder.name;
this.age = builder.age;
this.height = builder.height;
this.weight = builder.weight;
}改造Builder类，关键步骤是将各个set方法返回Builder类对象，这样就能继续愉快地连续调用set方法了，最后调用build()创建方法返回Person对象。
static class Builder{
private String name;
private int age;
private float height;
private float weight;
public Builder setName(String name) {
this.name = name;
return this;
}
public Builder setAge(int age) {
this.age = age;
return this;
}
public Builder setHeight(float height) {
this.height = height;
return this;
}
public Builder setWeight(float weight) {
this.weight = weight;
return this;
}
public Person build(){
return new Person(this);
}
}将各个set方法的返回值类型改为Builder，每次都返回builder对象，这样才能将set方法实现连续的链式调用。
build()方法创建一个person对象，会调用Person的带参构造方法，将builder对象的属性依次赋予person对象。person中的属性值就是链式调用set方法的各个值。
使用Builder模式创建Person对象，明显看出代码可读性大大增强。注：Builder创建方式通常是在创建的对象少的情况下使用。
Person person = new Person.Builder()
.setName("莉哥")
.setAge(20)
.setHeight(162)
.setWeight(45)
.build();关于如何使用Builder方式创建一个对象问题的解答就分享到这里了，希望以上内容可以对大家有一定的帮助，如果你还有很多疑惑没有解开，可以关注创新互联行业资讯频道了解更多相关知识。