Java beans call instances through map's api-javaTutorial-php.cn

Java beans call instances through map's api

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Release： 2017-07-20 14:18:53

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1. org.apache.commons.beanutils.BeanMap;

Allows a java bean to be called through the map api,

Several Supported operation interfaces:

Object get(Object key)
Object put(Object key, Object value)
void putAll(Map t)
Set entrySet()
Collection values()
boolean containsKey(Object key)
....

For example :

//将student的信息拼成字符串，格式：stuname|stuage|stuclass
protected String getLine(Student student) {
           StringBuilder sb = new StringBuilder();
           BeanMap map = new BeanMap(student );
           appStr(sb, map, "stuname");
           appStr(sb, map, "stuage");
           appStr(sb, map, "stuclass");
           return sb.toString();
     }
 
//将teacher的信息拼成字符串，格式：tname|tage|tclass
protected String getLine(Teacher teacher) {
           StringBuilder sb = new StringBuilder();
           BeanMap map = new BeanMap(teacher);
           appStr(sb, map, "tname");
           appStr(sb, map, "tage");
           appStr(sb, map, "tclass");
           return sb.toString();
     }
     
 
//拼字符串公用方法，将不同的对象，比如studengt和teacher的信息通过map传到方法里
protected void appStr(StringBuilder sb, Map<String, Object> map,
                String str) {
           Object value = map.get(str);
           sb.append(newValue).append("|");
     }

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Note: In the above example, although

can be used directly

sb.append(student.getStuname()).append("|").append(student.getStuage()).append("|").append(student.getStuclass);

To splice strings, but use BeanMap. I think the reason is that there are multiple objects (such as student, teacher, etc.) that need to use the method of splicing strings at the same time.

I want to abstract the public method , so BeanMap is used, so there is no need to pass every object to appStr, only one BeanMap object is required.

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