java 字符串占位符替换之字符串占位符实现(java简单模板渲染实现)

简单实现

关于java字符串占位符替换,专业方式是使用String.format和MessageFormat.format功能,这里提供个简单的基于正则实现的字符串占位符实现

public static String tpl(String tplStr,Map<String, Object> data ) {
Matcher m=Pattern.compile("\\{([\\w\\.]*)\\}").matcher(tplStr);
while(m.find()){
String group=m.group();
group= group.replaceAll("\\{|\\}", "");
String value="";
if(null!=data.get(group)){
value=String.valueOf(data.get(group));
}
tplStr=tplStr.replace(m.group(),value);
}
return tplStr;
}

使用freemarker等模板引擎

private String defaultCharacter = "UTF-8";
private Configuration cfg;
public FreemarkerUtils() {
cfg = new Configuration();
cfg.setDefaultEncoding(defaultCharacter);
cfg.setTagSyntax(Configuration.AUTO_DETECT_TAG_SYNTAX);
}
public  String generateString(
Map<String, Object> data,  String tplStr) {
String result = null;
String name="myStrTpl";
try {
StringTemplateLoader stringTemplateLoader= new StringTemplateLoader();
stringTemplateLoader.putTemplate(name, tplStr);
cfg.setTemplateLoader(stringTemplateLoader);
Template template = cfg.getTemplate(name,defaultCharacter);
StringWriter out = new StringWriter();
template.process(data, out);
out.flush();
result= out.toString();
out.close();
} catch (Exception e) {
e.printStackTrace();
}
return result;
}