csdn技术中心 java集合框架 (一).htm

javn的Java书籍JAVA集合框架.rar我看过了是很有帮助的

            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'">(4)<SPAN 
            style="mso-tab-count: 1"> </SPAN></SPAN><CODE><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">Collection</SPAN></CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt">转换为</SPAN><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">Object</SPAN></CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt">数组 
            </SPAN><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt">：</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt"><o:p></o:p></SPAN></P>
            <P class=MsoNormal 
            style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt"><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">Object[] 
            toArray() </SPAN></CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt">：返回一个内含集合所有元素的</SPAN><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">array<o:p></o:p></SPAN></CODE></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt 21pt"><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">Object[] 
            toArray(Object[] a) </SPAN></CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt">：</SPAN><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt">返回一个内含集合所有元素的</SPAN><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">array</SPAN></CODE><CODE><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体">。</SPAN></CODE><CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt">运行期返</SPAN></CODE><CODE><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体">回的</SPAN></CODE><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">array</SPAN></CODE><CODE><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体">和参数</SPAN></CODE><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">a</SPAN></CODE><CODE><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体">的型别相同，需要转换为正确型别。<SPAN 
            lang=EN-US><o:p></o:p></SPAN></SPAN></CODE></P>
            <P class=MsoBodyTextIndent style="MARGIN: 0cm 0cm 0pt"><FONT 
            size=2><FONT face=宋体><SPAN 
            style="mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">此外，您还可以把集合转换成其它任何其它的对象数组。但是，您不能直接把集合转换成基本数据类型的数组，因为集合必须持有对象。</SPAN><CODE><SPAN 
            lang=EN-US 
            style="COLOR: black; FONT-FAMILY: 'Times New Roman'; mso-bidi-font-family: 'Arial Unicode MS'; mso-fareast-font-family: 宋体"><o:p></o:p></SPAN></CODE></FONT></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt">『<I>斜体接口方法</I>是可选的。因为一个接口实现必须实现所有接口方法，调用程序就需要一种途径来知道一个可选的方法是不是不受支持。如果调用一种可选方法时，一个 
            </SPAN><CODE><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">UnsupportedOperationException</SPAN></CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt"> 
            被抛出，则操作失败，因为方法不受支持。此异常类继承 </SPAN><CODE><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">RuntimeException</SPAN></CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt"> 
            类，避免了将所有集合操作放入 </SPAN><CODE><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">try-catch</SPAN></CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt"> 
            块。』<o:p></o:p></SPAN></P>
            <P class=MsoBodyTextIndent style="MARGIN: 0cm 0cm 0pt"><FONT 
            size=2><SPAN lang=EN-US 
            style="COLOR: black; FONT-FAMILY: 'Courier New'">Collection</SPAN><SPAN 
            style="COLOR: black"><FONT face=宋体>不提供</FONT></SPAN><SPAN lang=EN-US 
            style="COLOR: black; FONT-FAMILY: 'Courier New'">get()</SPAN><SPAN 
            style="COLOR: black"><FONT face=宋体>方法。如果要遍历</FONT></SPAN><SPAN 
            lang=EN-US 
            style="COLOR: black; FONT-FAMILY: 'Courier New'">Collectin</SPAN><SPAN 
            style="COLOR: black"><FONT face=宋体>中的元素，就必须用</FONT></SPAN><SPAN 
            lang=EN-US 
            style="COLOR: black; FONT-FAMILY: 'Courier New'">Iterator</SPAN><SPAN 
            style="COLOR: black"><FONT face=宋体>。</FONT></SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><B><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; FONT-FAMILY: Verdana; mso-bidi-font-size: 12.0pt">1.1.AbstractCollection</SPAN></B><B><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt"> 
            抽象类</SPAN></B><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt"> 
            <o:p></o:p></SPAN></P>
            <P class=MsoNormal 
            style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt"><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">AbstractCollection</SPAN></CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt"> 
            类提供具体“集合框架”类的基本功能。虽然您可以自行实现 </SPAN><CODE><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">Collection</SPAN></CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt"> 
            接口的所有方法，但是，除了</SPAN><CODE><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">iterator()</SPAN></CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt">和</SPAN><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">size()</SPAN></CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt">方法在恰当的子类中实现以外，其它所有方法都由 
            </SPAN><CODE><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">AbstractCollection</SPAN></CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt"> 
            类来提供实现。如果子类不覆盖某些方法，可选的如</SPAN><CODE><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 'Courier New'; mso-fareast-font-family: 宋体">add()</SPAN></CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt">之类的方法将抛出异常。<SPAN 
            lang=EN-US><o:p></o:p></SPAN></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><B><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana">1.2.Iterator 
            </SPAN></B><B><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">接口</SPAN></B><B><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana"><o:p></o:p></SPAN></B></P>
            <P class=MsoNormal 
            style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt"><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">Collection</SPAN></CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana"> 
            </SPAN><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">接口的</SPAN><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier; mso-bidi-font-family: 'Times New Roman'; mso-fareast-font-family: 宋体">iterator()</SPAN></CODE><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">方法返回一个</SPAN><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana"> 
            </SPAN><CODE><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">Iterator</SPAN></CODE><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">。</SPAN><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">Iterator</SPAN></CODE><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">接口方法能以迭代方式逐个访问集合中各个元素，并安全的从</SPAN><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">Collection</SPAN></CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana"> 
            </SPAN><SPAN 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体; mso-ascii-font-family: Verdana; mso-hansi-font-family: Verdana">中除去适当的元素。</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana"><o:p></o:p></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: center" 
            align=center><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Verdana"><o:p></o:p></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt" 
            align=center><CODE><SPAN lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier"><IMG 
            alt="" hspace=0 
            src="CSDN技术中心 Java集合框架 (一).files/CSDN_Dev_Image_2003-11-30926016.jpg" 
            align=absMiddle border=0></SPAN></CODE></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">(1)<SPAN 
            style="mso-tab-count: 1"> </SPAN>boolean hasNext(): 
            </SPAN></CODE><CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt">判断是否存在另一个可访问的元素</SPAN></CODE><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体"><o:p></o:p></SPAN></CODE></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt 18.75pt"><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">Object 
            next(): </SPAN></CODE><CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt">返回要访问的下一个元素。如果到达集合结尾，则抛出</SPAN></CODE><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">NoSuchElementException</SPAN></CODE><CODE><SPAN 
            style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt">异常。</SPAN></CODE><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体"><o:p></o:p></SPAN></CODE></P>
            <P class=MsoNormal 
            style="MARGIN: 0cm 0cm 0pt 18.75pt; TEXT-INDENT: -18.75pt"><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier">(2)<SPAN 
            style="mso-tab-count: 1"> </SPAN>void <SPAN 
            style="mso-spacerun: yes">&nbsp;</SPAN></SPAN></CODE><CODE><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: Courier; mso-bidi-font-family: 'Times New Roman'; mso-fareast-font-family: 宋体">remove(): 
            </SPAN></CODE