JsonUtils工具类
import java.beans.IntrospectionException;import java.beans.Introspector;import java.beans.PropertyDescriptor;import java.math.BigDecimal;import java.math.BigInteger;import java.util.List;import java.util.Map;import java.util.Set;public class JsonUtils{ /** Commons Logging instance. */ private static org.apache.commons.logging.Log log = org.apache.commons.logging.LogFactory.getLog(JsonUtils.class); /** * @param obj 任意对象 * @return String */ public static String object2json(Object obj) { StringBuilder json = new StringBuilder(); if (obj == null) { json.append(""""); } else if (obj instanceof String || obj instanceof Integer || obj instanceof Float || obj instanceof Boolean || obj instanceof Short || obj instanceof Double || obj instanceof Long || obj instanceof BigDecimal || obj instanceof BigInteger || obj instanceof Byte) { json.append(""").append(string2json(obj.toString())).append("""); } else if (obj instanceof Object[]) { json.append(array2json((Object[]) obj)); } else if (obj instanceof List) { json.append(list2json((List<?>) obj)); } else if (obj instanceof Map) { json.append(map2json((Map<?, ?>) obj)); } else if (obj instanceof Set) { json.append(set2json((Set<?>) obj)); } else { json.append(bean2json(obj)); } return json.toString(); } /** * @param bean bean对象 * @return String */ public static String bean2json(Object bean) { StringBuilder json = new StringBuilder(); json.append("{"); PropertyDescriptor[] props = null; try { props = Introspector.getBeanInfo (bean.getClass(), Object.class).getPropertyDescriptors(); } catch (IntrospectionException e) { e.printStackTrace(); } if (props != null) { for (int i = 0; i < props.length; i++) { try { String name = object2json(props[i].getName()); String value = object2json(props[i].getReadMethod().invoke(bean)); json.append(name); json.append(":"); json.append(value); json.append(","); } catch (Exception e) { e.printStackTrace(); } } json.setCharAt(json.length() - 1, '}'); } else { json.append("}"); } return json.toString(); } /** * @param list list对象 * @return String */ public static String list2json(List<?> list) { StringBuilder json = new StringBuilder(); json.append("["); if (list != null && list.size() > 0) { for (Object obj : list) { json.append(object2json(obj)); json.append(","); } json.setCharAt(json.length() - 1, ']'); } else { json.append("]"); } return json.toString(); } /** * @param array 对象数组 * @return String */ public static String array2json(Object[] array) { StringBuilder json = new StringBuilder(); json.append("["); if (array != null && array.length > 0) { for (Object obj : array) { json.append(object2json(obj)); json.append(","); } json.setCharAt(json.length() - 1, ']'); } else { json.append("]"); } return json.toString(); } /** * @param map map对象 * @return String */ public static String map2json(Map<?, ?> map) { StringBuilder json = new StringBuilder(); json.append("{"); if (map != null && map.size() > 0) { for (Object key : map.keySet()) { json.append(object2json(key)); json.append(":"); json.append(object2json(map.get(key))); json.append(","); } json.setCharAt(json.length() - 1, '}'); } else { json.append("}"); } return json.toString(); } /** * @param set 集合对象 * @return String */ public static String set2json(Set<?> set) { StringBuilder json = new StringBuilder(); json.append("["); if (set != null && set.size() > 0) { for (Object obj : set) { json.append(object2json(obj)); json.append(","); } json.setCharAt(json.length() - 1, ']'); } else { json.append("]"); } return json.toString(); } /** * @param s 参数 * @return String */ public static String string2json(String s) { if (null == s){ return ""; } StringBuilder sb = new StringBuilder(); for (int i = 0; i < s.length(); i++) { char ch = s.charAt(i); switch (ch) { case '"': sb.append("\\""); break; case '\\': sb.append("\\\"); break; case '\b': sb.append("\\b"); break; case '\f': sb.append("\\f"); break; case '\n': sb.append("\\n"); break; case '\r': sb.append("\\r"); break; case '\t': sb.append("\\t"); break; case '/': sb.append("\\/"); break; default: if (ch >= '\u0000' && ch <= '\u001F') { String ss = Integer.toHexString(ch); sb.append("\\u"); for (int k = 0; k < 4 - ss.length(); k++) { sb.append('0'); } sb.append(ss.toUpperCase()); } else { sb.append(ch); } } } return sb.toString(); }} ?