好久没有更新了,偷懒,该打!
1、这个是一个基本的文件操作,实现对文件读取、写入一个数字的操作的
package trying;
import java.io.*;
/**
* @author gooing
*/
public class FileRw {
private File f = new File("d:\\j2\\a.txt");
public int getNum(){
int i = -1;
try{
String stri="";
BufferedReader in = new BufferedReader(new FileReader(f));
while((stri=in.readLine())!=null){
i = Integer.parseInt(stri.trim());
}
in.close();
}catch(Exception e){
e.printStackTrace();
}
return i;
}
public void setNum(){
int i = getNum();
i++;
try{
PrintWriter out=new PrintWriter(new BufferedWriter(new FileWriter(f,false)));
out.write(String.valueOf(i));
//可能是编码的原因,如果直接写入int的话,将出现java编码和windows编码的混乱,因此此处写入的是String
out.close() ;
}catch(Exception e){
e.printStackTrace();
}
}
public static void main(String[] args) {
FileRw frw = new FileRw();
for(int i =0;i<100; i++){
frw.setNum();
System.out.println(frw.getNum());
}
}
}
2、下面这个是学习工厂模式的一个例子
//Garden.java实现一个抽象花园工厂,你可以从中得到该花园的中心植物和周边植物;
//当然,对于不同的花园而言,其中心植物和周边植物是不一样的
package pkgfactory;
/**
* @author gooing TODO To change the template for this generated type
* comment go to Window - Preferences - Java - Code Style - Code
* Templates
*/
public abstract class Garden {
public abstract Plant getCenter();
public abstract Plant getBorder();
public void memo() {
System.out.println("CenterPlant:" + getCenter().getName());
System.out.println("BorderPlant:" + getBorder().getName());
System.out.println("---------------------");
}
}
//Plant.java 实现对花园中植物的基本抽象,此处只提供一个植物的name属性
package pkgfactory;
public class Plant {
public Plant(String name) {
this.name = name;
}
public String getName() {
return name;
}
private String name;
}
//VerGarden.java 和FlowerGarden.java 分别实现了一个菜园子和花园子
package pkgfactory;
public class VegGarden extends Garden {
public Plant getCenter() {
return new Plant("Wheat");
}
public Plant getBorder() {
return new Plant("Carrot");
}
}
package pkgfactory;
public class FlowerGarden extends Garden {
public Plant getCenter() {
return new Plant("Rose");
}
public Plant getBorder() {
return new Plant("JuHua");
}
}
//Gardener.java是该例程的一个驱动
package pkgfactory;
public class Gardener {
public static void main(String[] args) {
Garden g1 = new FlowerGarden();
Garden g2 = new VegGarden();
g1.memo();
g2.memo();
}
}