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Java 教程

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数据类型 数字 布尔值 字符 现实生活中的例子 非基本类型
Java 类型转换 Java 运算符 Java 字符串
字符串 连接 数字和字符串 特殊字符
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if else else if if...else 简写 现实生活中的例子
Java switch Java while 循环
while 循环 do/while 循环 现实生活中的例子
Java for 循环
for 循环 嵌套循环 for-each 循环 现实生活中的例子
Java break/continue Java 数组
数组 遍历数组 现实生活中的例子 多维数组

Java 方法

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Java 文件处理

Java 文件 Java 创建/写入文件 Java 读取文件 Java 删除文件

Java 如何做

加两个数字 统计单词数量 反转字符串 数组元素的总和 将字符串转换为数组 对数组排序 查找数组平均值 查找最小元素 ArrayList 循环 HashMap 循环 遍历枚举 矩形的面积 偶数或奇数 正数或负数 平方根 随机数

Java 参考

Java 参考 Java 关键字
assert abstract boolean break byte case catch char class continue default do double else enum exports extends final finally float for if implements import instanceof int interface long module native new package private protected public return requires short static super switch synchronized this throw throws transient try var void volatile while
Java 字符串方法
charAt() codePointAt() codePointBefore() codePointCount() compareTo() compareToIgnoreCase() concat() contains() contentEquals() copyValueOf() endsWith() equals() equalsIgnoreCase() format() getBytes() getChars() hashCode() indexOf() isEmpty() join() lastIndexOf() length() matches() offsetByCodePoints() regionMatches() replace() replaceAll() replaceFirst() split() startsWith() subSequence() substring() toCharArray() toLowerCase() toString() toUpperCase() trim() valueOf()
Java 数学方法
abs() acos() addExact() asin() atan() atan2() cbrt() ceil() copySign() cos() cosh() decrementExact() exp() expm1() floor() floorDiv() floorMod() getExponent() hypot() IEEEremainder() incrementExact() log() log10() log1p() max() min() multiplyExact() negateExact() nextAafter() nextDown() nextUp() pow() random() rint() round() scalb() signum() sin() sinh() sqrt() subtractExact() tan() tanh() toDegrees() toIntExact() toRadians() ulp()
Java 输出方法
print() printf() println()
Java 数组方法
compare() equals() sort() fill() length
Java ArrayList 方法
add() addAll() clear() clone() contains ensureCapacity() forEach() get() indexOf() isEmpty() iterator() lastIndexOf() listIterator() remove() removeAll() removeIf() replaceAll() retainAll() set() size() sort() spliterator() subList() toArray() trimToSize()
Java LinkedList 方法
add() addAll() clear() clone() contains forEach() get() getFirst() getLast() indexOf() isEmpty() iterator() lastIndexOf() listIterator() remove() removeAll() removeFirst() removeIf() removeLast() replaceAll() retainAll() set() size() sort() spliterator() subList() toArray()
Java HashMap 方法
clear() clone() compute() computeIfAbsent() computeIfPresent() containsKey() containsValue() entrySet() forEach() get() getOrDefault() isEmpty() keySet() merge() put() putAll() putIfAbsent() remove() replace() replaceAll() size() values()
Java Scanner 方法
close() delimiter() findInLine() findWithinHorizon() hasNext() hasNextBoolean() hasNextByte() hasNextDouble() hasNextFloat() hasNextInt() hasNextLine() hasNextLong() hasNextShort() locale() next() nextBoolean() nextByte() nextDouble() nextFloat() nextInt() nextLine() nextLong() nextShort() radix() reset() useDelimiter() useLocale() useRadix()
Java 迭代器方法 Java 错误和异常

Java 示例

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Java 如何反转字符串

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反转字符串

您可以通过以下示例轻松地按字符反转字符串

示例

String originalStr = "Hello";
String reversedStr = "";

for (int i = 0; i < originalStr.length(); i++) {
  reversedStr = originalStr.charAt(i) + reversedStr;
}

System.out.println("Reversed string: "+ reversedStr);
自己尝试 »

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Java 字符串教程

Java 字符串方法


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