4.3 读取property文件

src/com/demo/tank/course4/MainV4.java

@@ -1,13 +1,15 @@
 package com.demo.tank.course4;
 
 import com.demo.tank.util.Audio;
+import com.demo.tank.util.PropertyManager;
 
 import java.io.IOException;
 
 public class MainV4 {
     public static void main(String[] args) throws InterruptedException, IOException {
         TankFrameV4 tf = new TankFrameV4();
-        for(int i = 0; i < 5; i++){
+        int enemyTankNum = PropertyManager.getInt("enemy.tank.number");
+        for(int i = 0; i < enemyTankNum; i++){
             tf.enemyTanks.add(new Tank(50 + i*80, 200, Direction.DOWN, Group.BAD, tf));
         }
 

src/com/demo/tank/util/PropertyManager.java

@@ -0,0 +1,22 @@
+package com.demo.tank.util;
+
+
+import java.io.IOException;
+import java.util.Properties;
+
+public class PropertyManager {
+    static Properties property = new Properties();
+
+    static {
+        try {
+            property.load(PropertyManager.class.getClassLoader().getResourceAsStream("config"));
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public static int getInt(String key){
+        if(property == null) return 0;
+        return Integer.valueOf((String)property.get(key));
+    }
+}

src/config

@@ -0,0 +1,5 @@
+enemy.tank.number=8
+tank.speed=5
+bullet.speed=5
+game.width=1080
+game.height=720