サンプルから学ぶJava言語の Boolean/String/boolean型の変換

import java.util.Properties;

public class TestConverter {

    /**
     * @param args
     */
    public static void main(String[] args) {
        System.out.println("**************String/boolean型→Boolean型：Boolean.valueOf**************");
        System.out.println("return Boolean:" + Boolean.valueOf("true"));
        System.out.println("return Boolean:" + Boolean.valueOf("false"));
        System.out.println("return Boolean:" + Boolean.valueOf("1"));
        System.out.println("return Boolean:" + Boolean.valueOf("0"));
        System.out.println("return boolean:" + Boolean.valueOf(true));
        System.out.println("return boolean:" + Boolean.valueOf(false));
        System.out.println("return boolean:" + Boolean.valueOf(null));
        
        System.out.println("**************String型→Boolean型：Boolean.getBoolean**************");
        Properties prop = System.getProperties();
        prop.setProperty("Logined", "true");
        //boolean ret = Boolean.getBoolean("true");
        //引数によって指定されたシステムプロパティが存在し、それが文字列 "true" に等しい場合にだけ、 true を返します
        System.out.println("return boolean:" + Boolean.getBoolean("true"));    //toBoolean(System.getProperty(value));
        System.out.println("return boolean:" + Boolean.getBoolean("false"));
        System.out.println("return boolean:" + Boolean.getBoolean("1"));
        System.out.println("return boolean:" + Boolean.getBoolean("0"));
        System.out.println("return boolean:" + Boolean.getBoolean("Logined")); //システムプロパティに存在しているかつ"true"であるので、trueで返します
        
        System.out.println("**************String型→boolean型：Boolean.parseBoolean**************");
        System.out.println("return boolean:" + Boolean.parseBoolean("true"));
        System.out.println("return boolean:" + Boolean.parseBoolean("false"));
        System.out.println("return boolean:" + Boolean.parseBoolean("1"));
        System.out.println("return boolean:" + Boolean.parseBoolean("0"));
        System.out.println("return boolean:" + Boolean.parseBoolean(null));
        
        System.out.println("**************Boolean型→String型：Boolean.toString**************");
        System.out.println("return String:" + Boolean.TRUE.toString());
        System.out.println("return String:" + Boolean.FALSE.toString());
        
        System.out.println("**************Boolean型→boolean型：Boolean.booleanValue**************");
        System.out.println("return boolean:" + Boolean.TRUE.booleanValue());
        System.out.println("return boolean:" + Boolean.FALSE.booleanValue());
    }

}