import java.util.HashMap;  import java.util.Map;  import org.slf4j.Logger;  import org.slf4j.LoggerFactory;  /** * 配置文件或模板中的占位符替换工具类 * Date: 15-5-8 * Time: 下午4:12 */  public class PlaceholderUtils {  private static final Logger logger = LoggerFactory.getLogger(PlaceholderUtils.class);  /** * Prefix for system property placeholders: "${" */  public static final String PLACEHOLDER_PREFIX = "${";  /** * Suffix for system property placeholders: "}" */  public static final String PLACEHOLDER_SUFFIX = "}";  public static String resolvePlaceholders(String text, Map<String, String> parameter) {  if (parameter == null || parameter.isEmpty()) {  return text;  }  StringBuffer buf = new StringBuffer(text);  int startIndex = buf.indexOf(PLACEHOLDER_PREFIX);  while (startIndex != -1) {  int endIndex = buf.indexOf(PLACEHOLDER_SUFFIX, startIndex + PLACEHOLDER_PREFIX.length());  if (endIndex != -1) {  String placeholder = buf.substring(startIndex + PLACEHOLDER_PREFIX.length(), endIndex);  int nextIndex = endIndex + PLACEHOLDER_SUFFIX.length();  try {  String propVal = parameter.get(placeholder);  if (propVal != null) {  buf.replace(startIndex, endIndex + PLACEHOLDER_SUFFIX.length(), propVal);  nextIndex = startIndex + propVal.length();  } else {  logger.warn("Could not resolve placeholder '" + placeholder + "' in [" + text + "] ");  }  } catch (Exception ex) {  logger.warn("Could not resolve placeholder '" + placeholder + "' in [" + text + "]: " + ex);  }  startIndex = buf.indexOf(PLACEHOLDER_PREFIX, nextIndex);  } else {  startIndex = -1;  }  }  return buf.toString();  }  public static void main(String[] args) {  String aa= "我们都是好孩子,${num}说是嘛？ 我觉得${people}是傻蛋!";  Map<String, String> map = new HashMap<String, String>();  map.put("num","小二比");  map.put("people","小明");  System.out.println(PlaceholderUtils.resolvePlaceholders(aa, map));  }  }