Java tutorial
/** * Copyright 2013, Big Switch Networks, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); you may * not use this file except in compliance with the License. You may obtain * a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. **/ package net.floodlightcontroller.loadbalancer; import java.io.IOException; import java.util.Collection; import net.floodlightcontroller.packet.IPv4; import com.fasterxml.jackson.core.JsonParseException; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.core.JsonToken; import com.fasterxml.jackson.databind.MappingJsonFactory; import org.restlet.resource.Delete; import org.restlet.resource.Get; import org.restlet.resource.Post; import org.restlet.resource.Put; import org.restlet.resource.ServerResource; import org.slf4j.Logger; import org.slf4j.LoggerFactory; public class MembersResource extends ServerResource { protected static Logger log = LoggerFactory.getLogger(MembersResource.class); @Get("json") public Collection<LBMember> retrieve() { ILoadBalancerService lbs = (ILoadBalancerService) getContext().getAttributes() .get(ILoadBalancerService.class.getCanonicalName()); String memberId = (String) getRequestAttributes().get("member"); if (memberId != null) return lbs.listMember(memberId); else return lbs.listMembers(); } @Put @Post public LBMember createMember(String postData) { LBMember member = null; try { member = jsonToMember(postData); } catch (IOException e) { log.error("Could not parse JSON {}", e.getMessage()); } ILoadBalancerService lbs = (ILoadBalancerService) getContext().getAttributes() .get(ILoadBalancerService.class.getCanonicalName()); String memberId = (String) getRequestAttributes().get("member"); if (memberId != null) return lbs.updateMember(member); else return lbs.createMember(member); } @Delete public int removeMember() { String memberId = (String) getRequestAttributes().get("member"); ILoadBalancerService lbs = (ILoadBalancerService) getContext().getAttributes() .get(ILoadBalancerService.class.getCanonicalName()); return lbs.removeMember(memberId); } protected LBMember jsonToMember(String json) throws IOException { MappingJsonFactory f = new MappingJsonFactory(); JsonParser jp; LBMember member = new LBMember(); try { jp = f.createJsonParser(json); } catch (JsonParseException e) { throw new IOException(e); } jp.nextToken(); if (jp.getCurrentToken() != JsonToken.START_OBJECT) { throw new IOException("Expected START_OBJECT"); } while (jp.nextToken() != JsonToken.END_OBJECT) { if (jp.getCurrentToken() != JsonToken.FIELD_NAME) { throw new IOException("Expected FIELD_NAME"); } String n = jp.getCurrentName(); jp.nextToken(); if (jp.getText().equals("")) continue; if (n.equals("id")) { member.id = jp.getText(); continue; } else if (n.equals("address")) { member.address = IPv4.toIPv4Address(jp.getText()); continue; } else if (n.equals("port")) { member.port = Short.parseShort(jp.getText()); continue; } else if (n.equals("connection_limit")) { member.connectionLimit = Integer.parseInt(jp.getText()); continue; } else if (n.equals("admin_state")) { member.adminState = Short.parseShort(jp.getText()); continue; } else if (n.equals("status")) { member.status = Short.parseShort(jp.getText()); continue; } else if (n.equals("pool_id")) { member.poolId = jp.getText(); continue; } log.warn("Unrecognized field {} in " + "parsing Members", jp.getText()); } jp.close(); return member; } }