2.多執行緒的應用場景
b:jvm的啟動是多執行緒的嗎
public class demo1_thread
for(int i = 0; i < 10000; i++)
}class demo
案例：public class demo2_thread
}class mythread extends thread
}public class demo3_thread
}class myrunnable implements runnable
}繼承thread
實現runnable介面
案例：package com.heima.thread;
public class demo4_thread
}}.start(); //4,開啟執行緒
//實現runnable介面
new thread(new runnable()
}}).start(); //4,開啟執行緒
}2.設定名字
public class demo1_name
public static void demo2()
}.start();
new thread()
}.start();
}public static void demo3()
};thread t2 = new thread()
};t1.setname("張三");
t2.setname("李四");
t1.start();
t2.start();
}public static void demo1()
}.start();
new thread("鳳姐")
}.start();
}public class demo2_currentthread
}.start();
new thread(new runnable()
}).start();
//設定主線程的名字
thread.currentthread().setname("我是主線程");
//直接寫在main方法中，獲取的是主線程
system.out.println(thread.currentthread().getname());
}案例:
public class demo3_sleep catch (interruptedexception e)
system.out.println(getname() + "...aaaaaaaaaa");}}
}.start();
new thread() catch (interruptedexception e)
system.out.println(getname() + "...bb");}}
}.start();
}public static void demo1() throws interruptedexception
}*thread類下的 setdaemon(boolean on)
, 設定乙個執行緒為守護執行緒, 該執行緒不會單獨執行, 當其他非守護執行緒都執行結束後, 自動退出
案例:public class demo4_daemon }};
thread t2 = new thread() }};
t2.setdaemon(true); //設定為守護執行緒
t1.start();
t2.start();
}public class demo5_join }};
thread t2 = new thread() catch (interruptedexception e)
}system.out.println(getname() + "...bb");}}
};t1.start();
t2.start();
}public class demo6_yield }
class mythread extends thread
system.out.println(getname() + "..." + i);
}}public class demo7_priority }};
thread t2 = new thread()}};
設定最大優先順序
t1.setpriority(thread.min_priority); //設定最小的執行緒優先順序
t2.setpriority(thread.max_priority); //設定最大的執行緒優先順序
t1.start();
t2.start();
}2.同步**塊
public class demo1_synchronized
}}.start();
new thread()
}}.start();
}class printer
}public void print2()
}} //定義的鎖類
class demo{}
public class demo2_synchronized
}}.start();
new thread()
}}.start();
}class printer2
public void print2(this)
}} 案例(靜態的同步方法):
public class demo2_synchronized
}}.start();
new thread()
}}.start();
}class printer2
public static void print2()
}public class demo3_ticket class ticket extends thread
system.out.println(getname() + "...這是第" + ticket-- + "號票");
}}}
案例(未加suo,出現賣負號票):
public class demo3_ticket class ticket extends thread
try catch (interruptedexception e)
system.out.println(getname() + "...這是第" + ticket-- + "號票");
}}}
案例(用同步實現):
public class demo3_ticket class ticket extends thread
try catch (interruptedexception e)
system.out.println(getname() + "...這是第" + ticket-- + "號票");}}
}案例:
public class demo4_ticket class myticket implements runnable
try catch (interruptedexception e)
system.out.println(thread.currentthread().getname() + "...這是第" + tickets-- + "號票");}}
}public class demo5_deadlock }}
}}.start();
new thread() }}
}}.start();
}
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