| /* |
| * Copyright 2009 Google 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 com.google.gwt.http.client; |
| |
| import java.util.LinkedHashMap; |
| import java.util.Map; |
| |
| /** |
| * Utility class to build a URL from components. |
| * |
| * TODO(jlabanca): Add a constructor that parses an existing URL |
| */ |
| public class UrlBuilder { |
| |
| /** |
| * The port to use when no port should be specified. |
| */ |
| public static final int PORT_UNSPECIFIED = Integer.MIN_VALUE; |
| |
| /** |
| * A mapping of query parameters to their values. |
| */ |
| private Map<String, String[]> listParamMap = new LinkedHashMap<String, String[]>(); |
| |
| private String protocol = "http"; |
| private String host = null; |
| private int port = PORT_UNSPECIFIED; |
| private String path = null; |
| private String hash = null; |
| |
| /** |
| * Build the URL and return it as an encoded string. |
| * |
| * @return the encoded URL string |
| */ |
| public String buildString() { |
| StringBuilder url = new StringBuilder(); |
| |
| // http:// |
| url.append(URL.encode(protocol)).append("://"); |
| |
| // http://www.google.com |
| if (host != null) { |
| url.append(URL.encode(host)); |
| } |
| |
| // http://www.google.com:80 |
| if (port != PORT_UNSPECIFIED) { |
| url.append(":").append(port); |
| } |
| |
| // http://www.google.com:80/path/to/file.html |
| if (path != null && !"".equals(path)) { |
| url.append("/").append(URL.encode(path).replace("?", "%3F").replace("#", "%23")); |
| } |
| |
| // Generate the query string. |
| // http://www.google.com:80/path/to/file.html?k0=v0&k1=v1 |
| char prefix = '?'; |
| for (Map.Entry<String, String[]> entry : listParamMap.entrySet()) { |
| for (String val : entry.getValue()) { |
| url.append(prefix) |
| .append(URL.encodeQueryString(entry.getKey())) |
| .append('='); |
| if (val != null) { |
| // Also encodes +,& etc. |
| url.append(URL.encodeQueryString(val)); |
| } |
| prefix = '&'; |
| } |
| } |
| |
| // http://www.google.com:80/path/to/file.html?k0=v0&k1=v1#token |
| if (hash != null) { |
| // Hash characters in the hash fragment must be encoded separately |
| // because URL.encode does not do that (issue #8396) |
| url.append("#").append(URL.encode(hash).replace("#", "%23")); |
| } |
| |
| return url.toString(); |
| } |
| |
| /** |
| * Remove a query parameter from the map. |
| * |
| * @param name the parameter name |
| */ |
| public UrlBuilder removeParameter(String name) { |
| listParamMap.remove(name); |
| return this; |
| } |
| |
| /** |
| * Set the hash portion of the location (ex. myAnchor or #myAnchor). |
| * |
| * @param hash the hash |
| */ |
| public UrlBuilder setHash(String hash) { |
| if (hash != null && hash.startsWith("#")) { |
| hash = hash.substring(1); |
| } |
| this.hash = hash; |
| return this; |
| } |
| |
| /** |
| * Set the host portion of the location (ex. google.com). You can also specify |
| * the port in this method (ex. localhost:8888). |
| * |
| * @param host the host |
| */ |
| public UrlBuilder setHost(String host) { |
| // Extract the port from the host. |
| if (host != null && host.contains(":")) { |
| String[] parts = host.split(":"); |
| if (parts.length > 2) { |
| throw new IllegalArgumentException( |
| "Host contains more than one colon: " + host); |
| } |
| try { |
| setPort(Integer.parseInt(parts[1])); |
| } catch (NumberFormatException e) { |
| throw new IllegalArgumentException("Could not parse port out of host: " |
| + host); |
| } |
| host = parts[0]; |
| } |
| this.host = host; |
| return this; |
| } |
| |
| /** |
| * <p> |
| * Set a query parameter to a list of values. Each value in the list will be |
| * added as its own key/value pair. |
| * |
| * <p> |
| * <h3>Example Output</h3> |
| * <code>?mykey=value0&mykey=value1&mykey=value2</code> |
| * </p> |
| * |
| * @param key the key |
| * @param values the list of values |
| */ |
| public UrlBuilder setParameter(String key, String... values) { |
| assertNotNullOrEmpty(key, "Key cannot be null or empty", false); |
| assertNotNull(values, |
| "Values cannot null. Try using removeParameter instead."); |
| if (values.length == 0) { |
| throw new IllegalArgumentException( |
| "Values cannot be empty. Try using removeParameter instead."); |
| } |
| listParamMap.put(key, values); |
| return this; |
| } |
| |
| /** |
| * Set the path portion of the location (ex. path/to/file.html). |
| * |
| * @param path the path |
| */ |
| public UrlBuilder setPath(String path) { |
| if (path != null && path.startsWith("/")) { |
| path = path.substring(1); |
| } |
| this.path = path; |
| return this; |
| } |
| |
| /** |
| * Set the port to connect to. |
| * |
| * @param port the port, or {@link #PORT_UNSPECIFIED} |
| */ |
| public UrlBuilder setPort(int port) { |
| this.port = port; |
| return this; |
| } |
| |
| /** |
| * Set the protocol portion of the location (ex. http). |
| * |
| * @param protocol the protocol |
| */ |
| public UrlBuilder setProtocol(String protocol) { |
| assertNotNull(protocol, "Protocol cannot be null"); |
| if (protocol.endsWith("://")) { |
| protocol = protocol.substring(0, protocol.length() - 3); |
| } else if (protocol.endsWith(":/")) { |
| protocol = protocol.substring(0, protocol.length() - 2); |
| } else if (protocol.endsWith(":")) { |
| protocol = protocol.substring(0, protocol.length() - 1); |
| } |
| if (protocol.contains(":")) { |
| throw new IllegalArgumentException("Invalid protocol: " + protocol); |
| } |
| assertNotNullOrEmpty(protocol, "Protocol cannot be empty", false); |
| this.protocol = protocol; |
| return this; |
| } |
| |
| /** |
| * Assert that the value is not null. |
| * |
| * @param value the value |
| * @param message the message to include with any exceptions |
| * @throws IllegalArgumentException if value is null |
| */ |
| private void assertNotNull(Object value, String message) |
| throws IllegalArgumentException { |
| if (value == null) { |
| throw new IllegalArgumentException(message); |
| } |
| } |
| |
| /** |
| * Assert that the value is not null or empty. |
| * |
| * @param value the value |
| * @param message the message to include with any exceptions |
| * @param isState if true, throw a state exception instead |
| * @throws IllegalArgumentException if value is null |
| * @throws IllegalStateException if value is null and isState is true |
| */ |
| private void assertNotNullOrEmpty(String value, String message, |
| boolean isState) throws IllegalArgumentException { |
| if (value == null || value.length() == 0) { |
| if (isState) { |
| throw new IllegalStateException(message); |
| } else { |
| throw new IllegalArgumentException(message); |
| } |
| } |
| } |
| } |