1.3 模板方法：泛型模板+ 函数式编程(Function:去掉接口)

1.3 模板方法：泛型模板+ 函数式编程(Function:去掉接口)

package demo.spring.boot.demospringboot;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.*;
import java.util.List;
import java.util.function.Function;
import java.util.stream.Collectors;


public class Test {

    private Logger logger = LoggerFactory.getLogger(getClass());

    /**
     * 使用了模板泛型方法，+ function 处理input留作后期实现
     *
     * @param sh
     * @param function
     * @param <T>
     * @return
     */
    public <T> T executeLinuxCmd(String sh, Function<InputStream, T> function) {
        String cmd = sh;
        logger.info("sh is :{}", cmd);
        Runtime run = Runtime.getRuntime();
        InputStream in = null;
        T result = null;
        try {
            Process process = run.exec(cmd);
            in = process.getInputStream();
            result = function.apply(in);
            in.close();
            process.destroy();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return result;
    }

    /**
     * 调用了模板方法，调用时实现逻辑
     *
     * @param sh
     * @return
     */
    public List<String> getResult(String sh) {
        return this.executeLinuxCmd(sh, inputStream -> {
            Reader reader = new InputStreamReader(inputStream);
            LineNumberReader lineNumberReader
                    = new LineNumberReader(reader);
            List<String> list;
            list = lineNumberReader.lines().collect(Collectors.toList());
            try {
                lineNumberReader.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return list;
        });
    }

    @org.junit.Test
    public void test() {
        List<String> list = this.getResult("ls");
        logger.info("result:{}", list);
    }
}