1.3.4 try-with-resources (TWR)

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;

public class CoinTWR {

    @SuppressWarnings("null")
    public static void main(String[] args) throws IOException {// 抛出异常
        
        /** 资源管理 **/
        try (FileInputStream fin = new FileInputStream("someFile.bin");
                ObjectInputStream in = new ObjectInputStream(fin)) {
            // ...
        }
        
        /** 改善了错误跟踪的能力（注意其中被抑制的NullPointerException简称NPE）
         * Ran As Java Application:
         * Exception in thread "main" java.lang.NullPointerException
         *             at cointest.CoinTWR.main(CoinTWR.java:21)
         */
        try (InputStream i = null) {
            i.available();
        }

    }
    
}