面试完了，把题发给大家参考下 - 黑马程序员技术交流社区

package exercises;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
public class Test {
public static void main(String[] args) throws Exception {
// reflectMap();
// mapDemo();
Res res = new Res();
new Thread() {
@Override
public void run() {
while (true) {
try {
Thread.sleep(500);
res.put();
} catch (InterruptedException e) {
}
}
}
}.start();
new Thread() {
@Override
public void run() {
while (true) {
try {
Thread.sleep(500);
res.out();
} catch (InterruptedException e) {
}
}
}
}.start();
}
private static void reflectMap() throws Exception {
Map<Integer, Integer> map = new HashMap<Integer, Integer>();
map.put(5, 23);
System.out.println(map);
Method methodPut = map.getClass().getMethod("put", Object.class,
Object.class);
methodPut.invoke(map, "abc", "bcd");
System.out.println(map);
}
private static void mapDemo() {
Map<String, Integer> map = new TreeMap<String, Integer>();
map.put("abc", 123);
map.put("bcd", 234);
map.put("cde", 345);
map.put("def", 456);
// 1
Set<String> set = map.keySet();
Iterator<String> it = set.iterator();
while (it.hasNext()) {
String key = it.next();
int value = map.get(key);
System.out.println(key + ":" + value);
}
// 2
Set<Map.Entry<String, Integer>> entrySet = map.entrySet();
Iterator<Map.Entry<String, Integer>> entryIt = entrySet.iterator();
while (entryIt.hasNext()) {
Map.Entry<String, Integer> me = entryIt.next();
String key = me.getKey();
int value = me.getValue();
System.out.println(key + ":" + value);
}
}
}
/**
* 起两个线程，操作共享数组，隔一段时间向里面添加数据
*
* @author always
*
*/
class Res {
private String name;
private String sex;
private boolean isFull = false;
public boolean flag = false;
public synchronized void put() throws InterruptedException {
if (isFull)
wait();
if (flag) {
name = "zhangsan";
sex = "nan";
} else {
name = "李四";
sex = "女";
}
flag = flag ? false : true;
isFull = true;
notify();
}
public synchronized void out() throws InterruptedException {
if (!isFull)
wait();
System.out.println(name + " :: " + sex);
isFull = false;
notify();
}
}

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