StringBuffer类

1父类:java.lang.Object  
2
3java.lang.StringBuffer1.StringBuffer构造方法1>StringBuffer()　　构造一个不带字符的字符缓冲区,其初始容量为16个字符2>StringBuffer(CharSequence seq)　　构造一个字符串缓冲区包含与接口CharSequence相同的字符　　接口CharSequence的实现类包括String类/StringBuffer类/StringBuilder类　　因此StringBuffer(String value)是可以的;3>StringBuffer(int capacity)　　指定初始容量的字符串缓冲区4>StringBuffer(String str)//见2>
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52.StringBuffer特有方法1>public StringBuffer append(int x)//(char value)//(boolean value)　　
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71.StringBuffer leo9257 = new StringBuffer("nanjing.");
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9　　2.System.out.println(leo9257);//nanjing.
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11　　3.leo9257.append("guiyang");
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13　　4.System.out.println(leo9257);//nanjing.guiyang
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15　　5.leo9257.append(true).append('@').append(2009);
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17　　6.System.out.println(leo9257);//nanjing.guiyangtrue@2009
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192>public StringBuffer insert(int off,String str)
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21   1.StringBuffer leo9257 = new StringBuffer("nanjing.");
22　　2.leo9257.insert(6, "guiyang");//nanjinguiyangg.在索引出插入
23　　3.leo9257.insert(8, "guiyang");//nanjing.guiyang 
24
253>public StringBuffer delete(int start,int end)
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271.StringBuffer leo9257 = new StringBuffer("nanjing.guiyang2009-201*");
28　　2.leo9257.delete(19,leo9257.length());//nanjing.guiyang2009
29
304>public StringBuffer reserve()
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32　　1.StringBuffer leo9257 = new StringBuffer("nanjing.guiyang2009-201*");
33　　2.leo9257.reverse();//*102-9002gnayiug.gnijnan
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355>public StringBuffer replace(int Start,int end,String str)　　
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371.StringBuffer leo9257 = new StringBuffer("nanjing...guiyang2009");
38　　 2.leo9257.replace(7, 9, "pukou");//nanjingpukou.guiyang2009
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406.eg

1/*
2 *
3 *将一句话的首字母都转为大写
4 *leo9257 is the man who stayed in nanjing for nearly nine years. 
5 */
6
7public class UpperCaseDeom {
8    public static void main(String[] args) {
9        String s = "leo9257 is the man who stayed in Nanjing for nearly 9 years.";
10        
11        StringBuffer ns = new StringBuffer();
12        
13        String[] words = s.split(" ");
14        
15        for (int i = 0; i < words.length; i++) {
16            String s0 = words[i].substring(0,1).toUpperCase()+words[i].substring(1);
17            ns.append(s0+" ");
18        }
19        System.out.println(ns);
20    }
21}

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