java - Create simple POJO classes (bytecode) at runtime (dynamically) -

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i've following scenario..

i writing tool run user-entered query against database , return result..

the simplest way return result as: list<string[]> need take step further.

i need create (at runtime) pojo (or dto) name , create fields , setters , getters , populate data returned , return user among .class file generated...

so idea here how create simple class(bytecode) @ runtime (dynamically) basic search , found many lib including apache bcel think need more simpler...

what think of that?

thanks.

creating simple pojo getters , setters easy if use cglib:

public static class<?> createbeanclass(     /* qualified class name */     final string classname,     /* bean properties, name -> type */     final map<string, class<?>> properties){      final beangenerator beangenerator = new beangenerator();      /* use our own hard coded class name instead of real naming policy */     beangenerator.setnamingpolicy(new namingpolicy(){         @override public string getclassname(final string prefix,             final string source, final object key, final predicate names){             return classname;         }});     beangenerator.addproperties(beangenerator, properties);     return (class<?>) beangenerator.createclass(); }

test code:

public static void main(final string[] args) throws exception{     final map<string, class<?>> properties =         new hashmap<string, class<?>>();     properties.put("foo", integer.class);     properties.put("bar", string.class);     properties.put("baz", int[].class);      final class<?> beanclass =         createbeanclass("some.classname", properties);     system.out.println(beanclass);     for(final method method : beanclass.getdeclaredmethods()){         system.out.println(method);     }  }

output:

class some.classname
public int[] some.classname.getbaz()
public void some.classname.setbaz(int[])
public java.lang.integer some.classname.getfoo()
public void some.classname.setfoo(java.lang.integer)
public java.lang.string some.classname.getbar()
public void some.classname.setbar(java.lang.string)

but problem is: have no way of coding against these methods, don't exist @ compile time, don't know you.


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