Java字符串格式化,{}占位符根据名字替换实例我就废话不多说了，⼤家还是直接看代码吧~import java.beans.PropertyDescriptor;import ng.reflect.Method;import java.util.HashMap;import java.util.Map;import java.util.regex.Matcher;import java.util.regex.Pattern;public class StringFormatUtil {private static final Pattern pattern = pile("\\{(.*?)\\}");private static Matcher matcher;/*** 格式化字符串字符串中使⽤{key}表⽰占位符** @param sourStr* 需要匹配的字符串* @param param* 参数集* @return*/public static String stringFormat(String sourStr, Map<String, Object> param) {String tagerStr = sourStr;if (param == null)return tagerStr;try {matcher = pattern.matcher(tagerStr);while (matcher.find()) {String key = matcher.group();String keyclone = key.substring(1, key.length() - 1).trim();Object value = param.get(keyclone);if (value != null)tagerStr = tagerStr.replace(key, value.toString());}}catch (Exception e){return null;}return tagerStr;}/*** 格式化字符串字符串中使⽤{key}表⽰占位符利⽤反射⾃动获取对象属性值 (必须有get⽅法)** @param sourStr 需要匹配的字符串** @return*/public static String stringFormat(String sourStr, Object obj) {String tagerStr = sourStr;matcher = pattern.matcher(tagerStr);if (obj == null)return tagerStr;PropertyDescriptor pd;Method getMethod;// 匹配{}中间的内容包括括号while (matcher.find()) {String key = matcher.group();String keyclone = key.substring(1, key.length() - 1).trim();try {pd = new PropertyDescriptor(keyclone, obj.getClass());getMethod = pd.getReadMethod();// 获得get⽅法Object value = getMethod.invoke(obj);if (value != null)tagerStr = tagerStr.replace(key, value.toString());} catch (Exception e) {// TODO Auto-generated catch block// Loggers.addException(e);}}return tagerStr;}/*** 格式化字符串 (替换所有) 字符串中使⽤{key}表⽰占位符** @param sourStr* 需要匹配的字符串* @param param* 参数集* @return*/public static String stringFormatAll(String sourStr, Map<String, Object> param) {String tagerStr = sourStr;if (param == null)return tagerStr;try {matcher = pattern.matcher(tagerStr);while (matcher.find()) {String key = matcher.group();String keyclone = key.substring(1, key.length() - 1).trim();Object value = param.get(keyclone);if (value != null)tagerStr = tagerStr.replace(key, value.toString());}}catch (Exception e){return null;}return tagerStr;}/*** 格式花字符串，按照占位符名字* 输⼊：sourStr = xxxxx{a}xxxx{b} ,param = {a:A,b:B}* 输出：targetStr = xxxxAxxxxB* @param sourStr* @param param* @return*/public static String stringFormat(String sourStr, JSONObject param) {String tagerStr = sourStr;if (param == null)return tagerStr;try {matcher = pattern.matcher(tagerStr);while (matcher.find()) {String key = matcher.group();String keyclone = key.substring(1, key.length() - 1).trim();Object value = param.get(keyclone);if (value != null)tagerStr = tagerStr.replace(key, value.toString());}}catch (Exception e){return null;}return tagerStr;}public static void main(String[] args) {// Map<String,Object> map = new HashMap<>();// map.put("id","111");// map.put("sss","ss");// JSONObject json = new JSONObject();// json.put("id","212");// json.put("fff","xxxx");// json.put("emmmmm",11);// stringFormat("sisas&{fff}_diwahwi%{id}{jio}",json);}}补充知识：java中占位符的使⽤⼆话不说，先上代码package com.string.format;public class StringFormat {//占位符%s，拼接sql,删除两个表中的数据，条件是字符串数组类型的idpublic static void formSql(String tableName,String tableName2,String...strings){//sql占位符 %s占位符String sql="delete from %s,%s where id in (%s)";//声明新的字符串String sqls="";//遍历字符串的参数数组for (String str : strings) {//将参数数组拼接成字符串，⽤逗号分割sqls += str + ",";}//拼接最后会多出个逗号，截取sqls=sqls.substring(0, sqls.length()-1);//format第⼀个sql参数为⽬标字符串，tableName,tableName2，为替换的两表的名字，sqls为删除数据的参数集合String s=String.format(sql, tableName,tableName2,sqls);//输出拼接后的sqlSystem.out.println(s);}public static void main(String[] args) {//传⼊参数为指定表名，和参数值StringFormat.formSql("user","role", "1","3","5","7","9","33");}}其实，传⼊的参数是数组类型的值，我们也可以按array[0],array[1]的⽅式插⼊参数，只是参数个数应⽤不灵活，还是使⽤数组的⽅式取值⽐较好，public static void format(){String st="%s的%s的价格是%f,是否售罄%c,占总销售的%d%%,库存%d,是否为畅销品%b";String s=String.format(st, "58优品","啤酒",3.5,'是',50,199,true);System.out.println(s);}public static void main(String[] args) {//传⼊参数为指定表名，和参数值//StringFormat.formSql("user","role", "1","3","5","7","9","33");format();}public static void format(){//String st="%s的%s的价格是%f,是否售罄%c,占总销售的%d%%,库存%d,是否为畅销品%b";//String s=String.format(st, "58优品","啤酒",3.5,'是',50,199,true);//System.out.println(s);SimpleDateFormat simple=new SimpleDateFormat("yyyy年MM⽉dd⽇ HH点mm分ss秒");String newDate=simple.format(new Date());String st1="%s的%s的价格是%s,是否售罄%s,占总销售的%s%%,库存%s,是否为畅销品%s,当前⽇期为%s"; String ss=String.format(st1, "58优品","啤酒","3.5",'是',"80","998","true",newDate);System.out.println(ss);}public static void main(String[] args) {//传⼊参数为指定表名，和参数值//StringFormat.formSql("user","role", "1","3","5","7","9","33");format();}/*%S字符串类型的占位符* %c字符类型的占位符* %b布尔类型的占位符* %d整数类型的占位符* %%百分⽐类型的占位符* %n换⾏类型的占位符* %t时间类型的占位符* c全部的⽇期时间类型* F年-⽉-⽇格式* D年/⽉/⽇格式* rHH:MM:SS格式12⼩时制**/以上这篇Java字符串格式化,{}占位符根据名字替换实例就是⼩编分享给⼤家的全部内容了，希望能给⼤家⼀个参考，也希望⼤家多多⽀持。
