1. 普通的饱汉式、饿汉式

package org.bighead.test2;public class TestPrivate {	private String str = "strPrivate";	private static final TestPrivate TESTPRIVATE = new TestPrivate();	// 饱汉式、饿汉式	private TestPrivate() {		super();		System.out.println(str);	}		public static TestPrivate getInstance(){		return TESTPRIVATE;	}		public void toPrint(){		System.out.println("私有构造-公开方法--单实例");	}}

反射创建实例、调用方法（实例可访问的）

package org.bighead.test2;import java.lang.reflect.Constructor;import java.lang.reflect.InvocationTargetException;public class TestDefaultSub  {		public static void main(String[] args) {		Class
     
       clazz = TestPrivate.class;		try {			Constructor
       constructor = clazz.getDeclaredConstructor();			constructor.setAccessible(true);			TestPrivate tp = (TestPrivate) constructor.newInstance();			tp.toPrint();		} catch (NoSuchMethodException e) {			e.printStackTrace();		} catch (InstantiationException e1) {			e1.printStackTrace();		} catch (IllegalAccessException e1) {			e1.printStackTrace();		} catch (InvocationTargetException e1) {			e1.printStackTrace();		}	}}
     

2. 并发也会影响