001// Copyright 2007, 2008, 2010 The Apache Software Foundation 002// 003// Licensed under the Apache License, Version 2.0 (the "License"); 004// you may not use this file except in compliance with the License. 005// You may obtain a copy of the License at 006// 007// http://www.apache.org/licenses/LICENSE-2.0 008// 009// Unless required by applicable law or agreed to in writing, software 010// distributed under the License is distributed on an "AS IS" BASIS, 011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012// See the License for the specific language governing permissions and 013// limitations under the License. 014 015package org.apache.tapestry5.internal.services; 016 017import java.io.IOException; 018import java.io.PrintWriter; 019 020import org.apache.tapestry5.ContentType; 021import org.apache.tapestry5.SymbolConstants; 022import org.apache.tapestry5.internal.InternalConstants; 023import org.apache.tapestry5.ioc.annotations.Symbol; 024import org.apache.tapestry5.json.JSONObject; 025import org.apache.tapestry5.services.ComponentEventResultProcessor; 026import org.apache.tapestry5.services.Response; 027 028/** 029 * Implementation of {@link ComponentEventResultProcessor} for {@link org.apache.tapestry5.json.JSONObject}, allowing a 030 * component event handler to return a JSONObject that will be sent directly to the client as the reply. This is often 031 * used with custom components that need a custom JSON response. 032 */ 033public class JSONObjectEventResultProcessor implements ComponentEventResultProcessor<JSONObject> 034{ 035 private final Response response; 036 037 private final String outputEncoding; 038 039 private final boolean compactJSON; 040 041 public JSONObjectEventResultProcessor(Response response, 042 043 @Symbol(SymbolConstants.CHARSET) 044 String outputEncoding, 045 046 @Symbol(SymbolConstants.COMPACT_JSON) 047 boolean compactJSON) 048 { 049 this.response = response; 050 this.outputEncoding = outputEncoding; 051 this.compactJSON = compactJSON; 052 } 053 054 public void processResultValue(JSONObject value) throws IOException 055 { 056 ContentType contentType = new ContentType(InternalConstants.JSON_MIME_TYPE, outputEncoding); 057 058 PrintWriter pw = response.getPrintWriter(contentType.toString()); 059 060 value.print(pw, compactJSON); 061 062 pw.close(); 063 } 064}