考虑如下情况：
有个字符串模板：
"Your name: ${name}, sex: ${sex}, email: ${info.email}, ..."
现在需要对其进行处理，用数据 user 对象 中对应的属性值替换相应的占位符，例如 ${name} 然后输出结果。其中 user 对象为：
{
name: string,
sex: string,
info: {
phone: string,
email: string,
}
}
如何实现类似效果？
用下面的方法即可：
import org.springframework.beans.BeanWrapper;
import org.springframework.beans.BeanWrapperImpl;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public static String replacePlaceHolders(String template, Object data) {
BeanWrapper wrapper = new BeanWrapperImpl(data);
Matcher matcher = Pattern.compile("\\$\\{([^}]+)}").matcher(template);
StringBuffer result = new StringBuffer();
while (matcher.find()) {
String placeholder = matcher.group(1);
Object value = wrapper.getPropertyValue(placeholder);
String replace = value != null ? value.toString() : "";
matcher.appendReplacement(result, replace);
}
matcher.appendTail(result);
return result.toString();
}
对于明确的属性值的替换，可以使用
PropertyPlaceholderHelper propertyPlaceholderHelper = new PropertyPlaceholderHelper("${", "}");
propertyPlaceholderHelper .replacePlaceholders(template, values);
例如：
public static void testProperties(){
Properties properties = new Properties();
properties.setProperty("name", "lisi");
properties.setProperty("age", "29");
PropertyPlaceholderHelper helper = new PropertyPlaceholderHelper("${","}");
String value = "My name is ${name} and I am ${age} years old.";
String result = helper.replacePlaceholders(value, properties);
System.out.println(result);
}