java stringBuffer
(1).stringBuffer和stringBuilder区别
stringBuffer是线程安全的,
stringBuilder速度更快
(2).简单的stringBuffer例子
StringBuffer sBuffer = new StringBuffer("高久峰是一个:"); sBuffer.append("傻逼"); System.out.println(sBuffer);
(3).stringBuffer反转字符串
StringBuffer sBuffer = new StringBuffer("abc"); System.out.println(sBuffer.reverse());
(4).stringBuffer delete删除字符/移除字符,start为开始字符串的索引位置,end为结束字符串的索引位置
StringBuffer sBuffer = new StringBuffer("gaojiufeng"); sBuffer = sBuffer.delete(3, 6); System.out.println(sBuffer);
gaojiufeng改为gaofeng
(5).stringBuffer在指定位置插入字符串
StringBuffer sBuffer = new StringBuffer("gaojiufeng"); sBuffer = sBuffer.insert(3, '+'); sBuffer = sBuffer.insert(7, '+'); System.out.println(sBuffer);
gaojiufeng改为gao+jiu+feng
(6).stringBuffer替换指定位置的字符串
StringBuffer sBuffer = new StringBuffer("gaojiufeng"); sBuffer = sBuffer.replace(3, 6, "-");
gaojiufeng改为gao-feng
(7).stringBuffer获取当前容量,默认java会分配指定大小,超过会自动扩容
StringBuffer sBuffer = new StringBuffer("gaojiufeng"); System.out.println(sBuffer.capacity());
(8).stringBuffer获取指定索引的值
StringBuffer sBuffer = new StringBuffer("gaojiufeng"); System.out.println(sBuffer.charAt(9));
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