Java中Class.forName和classloader都可以用来对类进行加载。
Class.forName除了将类的.class文件加载到jvm中之外，还会对类进行解释，执行类中的static块。
而classloader只干一件事情，就是将.class文件加载到jvm中，不会执行static中的内容，只有在newInstance才会去执行static块。
Class.forName(name,initialize,loader)带参数也可控制是否加载static块。并且只有调用了newInstance()方法采用调用构造函数，创建类的对象。
代码如下：
package com.mangosoft.java.reflect; /**
* Created by zhangshengjian on 2017/3/1.
*/
public class Line {
static {
System.out.println("static code executing: loading line...");
}
}
package com.mangosoft.java.reflect; /**
* Created by zhangshengjian on 2017/3/1.
*/
public class Point {
static {
System.out.println("static code executing: loading point...");
}
}
package com.mangosoft.java.reflect; /**
* classloader和Class.forName的区别
*
* Created by zhangshengjian on 2017/3/1.
*/
public class ClassLoaderAndForNameTest { public static void main(String[] args) {
String wholeNameLine = "com.mangosoft.java.reflect.Line";
String wholeNamePoint = "com.mangosoft.java.reflect.Point"; System.out.println("classloader testing...");
testClassLoader(wholeNameLine, wholeNamePoint);
System.out.println("---------------------------------------");
System.out.println("Class.forName testing...");
testForName(wholeNameLine, wholeNamePoint);
} //classloader
public static void testClassLoader(String wholeNameLine, String wholeNamePoint) {
ClassLoader loader = ClassLoader.getSystemClassLoader();
Class<?> line;
Class<?> point;
try {
line = loader.loadClass(wholeNameLine);
point = loader.loadClass(wholeNamePoint);
System.out.println("line " + line.getName());
System.out.println("point " + point.getName());
} catch (ClassNotFoundException e){
e.printStackTrace();
}
} //Class.forName
public static void testForName(String wholeNameLine, String wholeNamePoint) {
try {
Class line = Class.forName(wholeNameLine);
Class point = Class.forName(wholeNamePoint);
System.out.println("line " + line.getName());
System.out.println("point " + point.getName());
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
}
运行结果如下：