1.1Java 对连接操作 (+) 和其他对象转换成 string 提供了特殊的支持. 连接操作通过 StringBuilder 或者 StringBuffer 的 append()方法.
通过 toString()方法实现转换操作.
1.2 在 string 构造器里面放一个 null, 会导致空指针异常.
1.3 构造器
- publicString() {this.value = "".value; }
- publicString(String original) {this.value =original.value;this.hash =original.hash; }
3. public String(charvalue[]) {this.value =Arrays.copyOf(value, value.length); } Arrays.copyOf()方法内部调用的是 System.arraycopy
- public String(char value[], int offset, int count)
- public String(int[] codePoints, int offset, int count)
- public String(byte ascii[], int hibyte, int offset, int count)
- public String(byte ascii[], int hibyte)
- public String(byte bytes[], int offset, intlength, String charsetName)throws UnsupportedEncodingException
- public String(byte bytes[], int offset, int length, Charset charset)
- public String(bytebytes[], String charsetName)throws UnsupportedEncodingException
- public String(byte bytes[], Charset charset)
- public String(byte bytes[], int offset, int length)
- public String(byte bytes[])
- public String(StringBuffer buffer)
- public String(StringBuilder builder)
16. ***String(char[] value, boolean share) 这个很重要, 速度很快, 但共享 char 数组. 具体看实现.
1.4 内部方法
- public int length()
- public booleanisEmpty() {return value.length == 0; }
- public char charAt(int index)
来源: http://www.bubuko.com/infodetail-3253581.html