public static void main(String[] args) {
// TODO Auto-generated method stub
try {
MongoClient mc = new MongoClient("localhost");
DB db = mc.getDB("mydb");
DBCollection dbc = db.getCollection("books");
/*BasicDBObject book=
new BasicDBObject();
book.put("name", "자바의 정석");
book.put("pages", 600);
dbc.insert(book);
book=
new BasicDBObject();
book.put("name", "스프링4");
book.put("pages", 250);
dbc.insert(book);
book=
new BasicDBObject();
book.put("name", "JQuery");
book.put("pages", 150);
dbc.insert(book);
book=
new BasicDBObject();
book.put("name", "오라클 프로그램");
book.put("pages", 800);
dbc.insert(book);
book=
new BasicDBObject();
book.put("name", "AngularJS");
book.put("pages", 130);
dbc.insert(book);
book=
new BasicDBObject();
book.put("name", "MongoDB");
book.put("pages", 650);
dbc.insert(book);
book=
new BasicDBObject();
book.put("name", "Hadoop");
book.put("pages", 300);
dbc.insert(book);
book=
new BasicDBObject();
book.put("name", "HIVE");
book.put("pages", 350);
dbc.insert(book);
book=
new BasicDBObject();
book.put("name", "PIG");
book.put("pages", 650);
dbc.insert(book);
book=
new BasicDBObject();
book.put("name", "HTML5");
book.put("pages", 360);
dbc.insert(book);*/
String map =
"function(){"
+ "var category;"
+ "if(this.pages>=300){"
+ "category='Big Books';"
+ "}else{"
+ "category='Small Books';}"
+ "emit(category,{name:this.name});}";
String reduce =
"function(key,values){"
+ "var sum=0;"
+ "values.forEach(function(doc){"
+ "sum+=1;"
+ "});"
+ "return {books:sum};}";
MapReduceCommand cmd =
new MapReduceCommand(dbc, map, reduce, null, MapReduceCommand.OutputType.INLINE, null);
MapReduceOutput out = dbc.mapReduce(cmd);
for (DBObject o : out.results()) {
System.out.println(o.toString());
}
} catch (Exception ex) {
System.out.println(ex.getMessage());
}
}
