import?java.io.File;
import?java.io.FileWriter;
import?java.text.DecimalFormat;


public?class?Circle?implements?Geometricobject{
	private?double?radius=1.0;
	static?double?PI?=?3.14;
	DecimalFormat?df?=?new?DecimalFormat（“#.##“）;
	//無參構造方法
	public?Circle（）{

	}
	//有參構造方法
	public?Circle（double?radius）{
		this.radius?=?radius;
	}
	//訪問器
	public?double?getRadius（）{
		return?radius;
	}
	//修改器
	public?void?setRadius（double?radius）{
		this.radius?=?radius;
	}
	public?void?draw（）?{
		//?TODO?Auto-generated?method?stub
		
	}
	
	public?void?erase（）?{
		//?TODO?Auto-generated?method?stub
		
	}
	//求面積
	public?double?getArea（）?{
		return?PI?*?radius?*?radius;
	}
	//求周長
	public?double?getPrimeter（）?{
		return?2?*?PI?*?radius;
	}
	public?String?toString（）{
		return?“圓形的半徑：“+df.format（this.radius）+“?“;
	}
	public?void?writeToFile（File?f）?throws?Exception{
		FileWriter?fw?=?new?FileWriter（ftrue）;
		fw.write（“圓形半徑?“+df.format（radius）+“?面積?“+df.format（getArea（））+“?周長?“+df.format（getPrimeter（）））;
		fw.write（“\r\n“）;
		fw.close（）;
	}

}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2013-09-14?11:53??幾何圖形\
?????文件?????????301??2013-09-14?01:14??幾何圖形\.classpath
?????文件?????????381??2013-09-14?01:14??幾何圖形\.project
?????目錄???????????0??2013-09-14?11:53??幾何圖形\.settings\
?????文件?????????629??2013-09-14?01:14??幾何圖形\.settings\org.eclipse.jdt.core.prefs
?????目錄???????????0??2013-09-14?11:53??幾何圖形\bin\
?????文件????????1921??2013-09-14?01:15??幾何圖形\bin\Circle.class
?????文件?????????284??2013-09-14?01:15??幾何圖形\bin\Geometricobject.class
?????目錄???????????0??2013-09-14?11:53??幾何圖形\bin\GUI\
?????文件?????????900??2013-09-14?11:36??幾何圖形\bin\GUI\Circle.class
?????文件?????????805??2013-09-14?11:36??幾何圖形\bin\GUI\Face.class
?????文件????????1056??2013-09-14?11:36??幾何圖形\bin\GUI\Panel$1.class
?????文件????????1802??2013-09-14?11:36??幾何圖形\bin\GUI\Panel$2.class
?????文件????????1817??2013-09-14?11:36??幾何圖形\bin\GUI\Panel$3.class
?????文件????????1465??2013-09-14?11:36??幾何圖形\bin\GUI\Panel$4.class
?????文件????????1512??2013-09-14?11:36??幾何圖形\bin\GUI\Panel$5.class
?????文件????????3725??2013-09-14?11:36??幾何圖形\bin\GUI\Panel.class
?????文件?????????931??2013-09-14?11:36??幾何圖形\bin\GUI\Rectangle.class
?????文件????????1394??2013-09-14?11:36??幾何圖形\bin\GUI\Triangle.class
?????文件????????1948??2013-09-14?01:15??幾何圖形\bin\Rectangle.class
?????文件????????2772??2013-09-14?02:22??幾何圖形\bin\TestGeometricobject2.class
?????文件????????2427??2013-09-14?01:15??幾何圖形\bin\Triangle.class
?????文件?????????194??2013-09-14?11:25??幾何圖形\Geometricobjects.txt
?????目錄???????????0??2013-09-14?11:53??幾何圖形\src\
?????文件????????1126??2013-09-14?01:15??幾何圖形\src\Circle.java
?????文件?????????344??2013-09-14?01:15??幾何圖形\src\Geometricobject.java
?????目錄???????????0??2013-09-14?11:53??幾何圖形\src\GUI\
?????文件????????7485??2013-09-14?11:36??幾何圖形\src\GUI\Face.java
?????文件????????1024??2013-09-14?01:15??幾何圖形\src\Rectangle.java
?????文件????????1732??2013-09-14?02:22??幾何圖形\src\TestGeometricobject2.java
?????文件????????1641??2013-09-14?01:15??幾何圖形\src\Triangle.java
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