Update

src/反射/GetConstructorMain.java

+package 反射;
+
+// !/usr/bin/env jdk1.8
+// encoding:utf-8
+//@software:IntelliJ IDEA
+//@pack:反射
+//@user:彭友聪
+//@date:2019/6/28
+//@time:19:35
+//@project:IDEA_JAVA
+//@file:GetConstuctorMain.java
+//Author:御承扬
+//email:2923616405@qq.com
+
+import java.lang.reflect.Constructor;
+
+
+public class GetConstructorMain {
+    private GetConstructorMain() {
+
+    }
+
+    public static void main(String[] args) {
+        GetConstructorTest example = new GetConstructorTest( "10", "20", "30" );
+        Class<? extends GetConstructorTest> exampleC = example.getClass();
+        // 获得所有构造方法
+        Constructor[] declaredConstructors = exampleC.getDeclaredConstructors();
+        int len = declaredConstructors.length;
+        for (int i = 0; i < len; i++) {
+            Constructor<?> constructor = declaredConstructors[i];
+            System.out.println( "查看是否允许带有可变数量的参数：" + constructor.isVarArgs() );
+            System.out.println( "该构造方法的入口参数类型依次为：" );
+            // 获得所有参数类型
+            Class[] parameterTypes = constructor.getParameterTypes();
+            for (Class parameterType : parameterTypes) {
+                System.out.println( " " + parameterType );
+            }
+            System.out.println( "该构造方法可能抛出的异常类型：" );
+            //  获得所有可能抛出的异常信息类型
+            Class[] exceptionTypes = constructor.getExceptionTypes();
+            for (Class exceptionType : exceptionTypes) {
+                System.out.println( " " + exceptionType );
+            }
+            GetConstructorTest example2 = null;
+            while (example2 == null) {
+                try {
+                    if (i == 2)
+                        example2 = (GetConstructorTest) constructor.newInstance();
+                    else if (i == 1)
+                        example2 = (GetConstructorTest) constructor.newInstance( "7", 5 );
+                    else {
+                        Object[] parameters = new Object[]{new String[]{"100", "200", "300"}};
+                        example2 = (GetConstructorTest) constructor.newInstance( parameters );
+                    }
+                } catch (Exception e) {
+                    System.out.println( "在创建对象时抛出异常，下面执行 setAccessible()" );
+                    // 设置允许访问
+                    constructor.setAccessible( true );
+                }
+            }
+            example2.print();
+            System.out.println();
+        }
+    }
+}

src/反射/GetConstructorTest.java

+package 反射;
+
+// !/usr/bin/env jdk1.8
+// encoding:utf-8
+//@software:IntelliJ IDEA
+//@pack:反射
+//@user:彭友聪
+//@date:2019/6/28
+//@time:19:17
+//@project:IDEA_JAVA
+//@file:GetConstructorTest.java
+//Author:御承扬
+//email:2923616405@qq.com
+
+
+import org.jetbrains.annotations.Contract;
+
+public class GetConstructorTest {
+    String s; // 定义一个字符串变量
+    int i, i2, i3; // 定义 3 个 int 变量
+
+    /**
+     * 默认构造方法
+     */
+    @Contract(pure = true)
+    private GetConstructorTest() {  // 无参构造函数
+
+    }
+
+    protected GetConstructorTest(String s, int i) { // 有参构造函数，用来为字符串变量和 int 变量初始化值
+        this.s = s;
+        this.i = i;
+    }
+
+    public GetConstructorTest(String... strings) throws NumberFormatException {
+        if (strings.length > 0)
+            i = Integer.valueOf( strings[0] );
+        if (strings.length > 1)
+            i2 = Integer.valueOf( strings[1] );
+        if (strings.length > 2)
+            i3 = Integer.valueOf( strings[2] );
+    }
+
+    public void print() {
+        System.out.println( "s="+s );
+        System.out.println( "i="+i );
+        System.out.println( "i2="+i2 );
+        System.out.println( "i3="+i3 );
+    }
+}