javaBean问题，高手来啊 - 黑马程序员技术交流社区

public class JavaBean {
boolean Boolean;
int Integer;
String s;
double Double;
public boolean isBoolean() {
return Boolean;
}
public void setBoolean(boolean b) {
Boolean = b;
}
public int getInteger() {
return Integer;
}
public void setInteger(int integer) {
Integer = integer;
}
public String getS() {
return s;
}
public void setS(String s) {
this.s = s;
}
public double getDouble() {
return Double;
}
public void setDouble(double d) {
Double = d;
}
public JavaBean(boolean b, int integer, String s, double d) {
super();
Boolean = b;
Integer = integer;
this.s = s;
Double = d;
}
public JavaBean() {
}
}

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public class user {
public static void main(String[] args) {
JavaBean jb = new JavaBean();
jb.setInteger(100);
jb.setS("www.itheima.com");
jb.setDouble(0.01D);
jb.setBoolean(true);
}
}

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/*
* 需求：存在一个JavaBean，它包含以下几种可能的属性：
*
1:boolean/Boolean
2:int/Integer
3:String
4:double/Double
属性名未知，现在要给这些属性设置默认值，以下是要求的默认值：
String类型的默认值为字符串 www.itheima.com
int/Integer类型的默认值为100
boolean/Boolean类型的默认值为true
double/Double的默认值为0.01D.
只需要设置带有getXxx/isXxx/setXxx方法的属性，非JavaBean属性不设置，请用代码实现
*/
package com.itheima;
import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
public class Test8 {
public static void main(String[] args) throws Exception {
Class<?> clazz = Class.forName("com.itheima.testBean" );
//得到一个与testBean相关联的类
Object bean = clazz.newInstance();
//创建此 Class 对象所表示的类的一个新实例
BeanInfo beanInfo = Introspector. getBeanInfo(clazz);
//在 Java Bean 上进行内省，了解其所有属性和公开的方法
PropertyDescriptor[] propertyDescriptors =
beanInfo.getPropertyDescriptors();
for(PropertyDescriptor pd : propertyDescriptors ){
Object name = pd.getName();
//获取属性名
Object type = pd.getPropertyType();
//获取属性类型
Method getMethod = pd .getReadMethod();
//获取get方法
Method setMethod = pd .getWriteMethod();
//获取set方法
if(!"class" .equals(name )){
if(setMethod != null) {
if(type == boolean.class || type == Boolean.class){
setMethod.invoke(bean , true);
// boolean/Boolean类型的默认值为true
}
if(type == String.class) {
setMethod.invoke(bean ,"www.iteima.com" );
//String类型的默认值为字符串 www.itheima.com
}
if(type == int.class || type == Integer. class){
setMethod.invoke(bean , 100);
// int/Integer类型的默认值为100
}
if(type == double.class || type == Double.class){
setMethod.invoke(bean , 0.01D);
}// double/Double的默认值为0.01D.
}
if(getMethod != null) {
System. out.println(type + " " + name + "=" +getMethod.invoke(bean, null) );
}
}
}
}}
class testBean {//testBean类的详情
private boolean b ;
private Integer i ;
private String str ;
private Double d ;
public boolean getB() {
return b ;
}
public void setB(boolean b) {
this.b = b ;
}
public Integer getI() {
return i ;
}
public void setI(Integer i) {
this.i = i ;
}
public String getStr() {
return str ;
}
public void setStr(String str) {
this.str = str ;
}
public Double getD() {
return d ;
}
public void setD(Double d) {
this.d = d ;
}
}

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