ObjectMapper mapper = new ObjectMapper();
MyObject obj = new MyObject();
String json = mapper.writeValueAsString(obj);
{
"field1": "value1",
"field2": 123,
"field3": {
"subfield1": "subvalue1",
"subfield2": "subvalue2"
}
}
ObjectMapper mapper = new ObjectMapper();
MyObject obj = new MyObject();
String json = mapper.writeValueAsString(obj);{"field1":"value1","field2":123,"field3":{"subfield1":"subvalue1","subfield2":"subvalue2"}}
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(1).java获取当前日期时间Date date = new Date(); System.out.println(date.toString());输出Fri Jul 02 10:29:55 CST 2021(2).java获取时间戳秒/毫秒D...
pattern表示正则表达式,接收正则表达式作为参数例子:String content = "my name is gaojiufeng"; String pattern = "....
java正则表达式的捕获组捕获组可以将匹配到的结果根据正则中的括号进行分组,这里变量我加了$符,php转java的坏习惯,懒得改了,能跑就行// 匹配字符串 String $line = "gaojiufeng 1994! ok?...
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假如有个字符串为"fatcatfatcatfat",正则为“cat”当调用appendReplacement(sb, "dog")时appendReplacement方法都会把匹配到的内容替换为dog,并把匹配到字符串的前面几个字符串+dog送给sb里,所以第...