java.lang.Boolean

/*
 * public final class Boolean extends Object implements Serializable,Comparable<Boolean>
 * Boolean类的对象中包装基本类型boolean的值。
 */
public class BooleanDmeo {

    public static void main(String[] args) {
        logicalAndDemo();
    }

    public static void fieldDemo() {
        // Boolean字段
        // public static final Boolean TRUE
        // public static final Boolean FALSE
        // public static final 类<Booolean> TYPE
        System.out.println(Boolean.FALSE);
        System.out.println(Boolean.TRUE);
        System.out.println(Boolean.TYPE);

    }

    public static void parseBooleanDemo() {
        // public static boolean parseBoolean(String s)
        // 将字符串解析为布尔值，
        // 当字符串不为null且等于（忽略大小写）“true”时，返回true
        // 其余情况返回false
        System.out.println(Boolean.parseBoolean(null));
        System.out.println(Boolean.parseBoolean("true"));
        System.out.println(Boolean.parseBoolean("false"));
        System.out.println(Boolean.parseBoolean("aaa"));
    }

    public static void booleanValueDemo() {
        // public boolean booleanValue()
        // 以Boolean元的形式返回此Boolean对象的值
        Boolean b1 = true;
        Boolean b2 = false;
        System.out.println(b1.booleanValue());
        System.out.println(b2.booleanValue());
    }

    public static void valueOfDemo() {
        // public static Boolean valueOf(boolean b)
        // 返回表示指定boolean值的Boolean实例。
        // 如果不需要新的Boolean实例，则通常应优先使用此方法，而不是构造函数
        // 此方法可能会产生明显更好的空间和时间性能
        Boolean b1 = true;
        Boolean b2 = false;
        System.out.println(Boolean.valueOf(b1));
        System.out.println(Boolean.valueOf(true));
        System.out.println("-----------");
        // public static Boolean valueOf(String s)
        System.out.println(Boolean.valueOf("true"));
    }

    public static void toStringDemo() {
        // public static String toString(boolean b)
        // 返回指定boolean的String对象
        System.out.println(Boolean.toString(true).getClass());
        System.out.println("-----------");
        Boolean b = false;
        System.out.println(b.toString());
    }

    public static void hashCodeDemo() {
        Boolean b1 = true;
        Boolean b2 = false;
        System.out.println(b1.hashCode());
        System.out.println(b2.hashCode());
        System.out.println("-----------");
        System.out.println(Boolean.hashCode(b1));
        System.out.println(Boolean.hashCode(b2));
    }

    public static void equalsDemo() {
        // public boolean equals(Object obj)
        Object o = true;
        Boolean b = false;
        System.out.println(b.equals(o));
    }

    public static void getBooleanDemo() {
        // public static boolean getBoolean(String name)
        // 当系统属性中，存在值等于true时，返回true
        // 否则返回false
        // name--键
        String key = "key";
        String value = "true";
        System.setProperty(key, value);
        System.out.println(Boolean.getBoolean(key));
    }

    public static void compareToDemo() {
        // public int compareTo(Boolean b)
        // 0--此对象表示与参数相同的布尔值
        // 1--此对象为true，参数为false
        // -1--此对象为false，参数为true
        Boolean b1 = true;
        Boolean b2 = true;
        Boolean b3 = false;
        System.out.println(b1.compareTo(b2));
        System.out.println(b1.compareTo(b3));
        System.out.println(b3.compareTo(b1));
    }

    public static void compareDemo() {
        // public static int compare(boolean x,boolean y)
        // 1--x为true，y为false
        // -1--x为false，y为true
        // 0--x与y布尔值相同
        Boolean b1 = true;
        Boolean b2 = true;
        Boolean b3 = false;
        System.out.println(Boolean.compare(b1, b3));
        System.out.println(Boolean.compare(b3, b1));
        System.out.println(Boolean.compare(b1, b1));
        System.out.println(Boolean.compare(b3, b3));
    }

    public static void logicalAndDemo() {
        // public static boolean logicalAnd(boolean a,boolean b)
        Boolean b1 = true;
        Boolean b2 = true;
        Boolean b3 = false;
        System.out.println(Boolean.logicalAnd(b1, b2));// 逻辑与
        System.out.println(Boolean.logicalOr(b1, b2));// 逻辑或
        System.out.println(Boolean.logicalXor(b1, b2));// 逻辑异或

    }
}