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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  package org.apache.omid;
19  
20  import com.google.common.base.Preconditions;
21  import com.google.common.io.Resources;
22  import org.apache.commons.beanutils.BeanUtils;
23  import org.slf4j.Logger;
24  import org.slf4j.LoggerFactory;
25  import org.yaml.snakeyaml.Yaml;
26  
27  import java.io.IOException;
28  import java.lang.reflect.InvocationTargetException;
29  import java.nio.charset.Charset;
30  import java.util.HashMap;
31  import java.util.Map;
32  
33  @SuppressWarnings("WeakerAccess")
34  public class YAMLUtils {
35  
36      private static final Logger LOG = LoggerFactory.getLogger(YAMLUtils.class);
37  
38      public void loadSettings(String resourcePath, String defaultResourcePath, Object bean) {
39          try {
40              Map properties = loadSettings(resourcePath, defaultResourcePath);
41              BeanUtils.populate(bean, properties);
42          } catch (IllegalAccessException | InvocationTargetException | IOException e) {
43              throw new IllegalStateException(e);
44          }
45      }
46  
47      public void loadSettings(String resourcePath, Object bean) {
48          try {
49              Map properties = loadSettings(null, resourcePath);
50              BeanUtils.populate(bean, properties);
51          } catch (IllegalAccessException | InvocationTargetException | IOException e) {
52              throw new IllegalStateException(e);
53          }
54      }
55  
56      @SuppressWarnings("unchecked")
57      public Map loadSettings(String resourcePath, String defaultResourcePath) throws IOException {
58          Map defaultSetting = loadAsMap(defaultResourcePath);
59          Preconditions.checkState(defaultSetting.size() > 0, String.format("Failed to load file '%s' from classpath", defaultResourcePath));
60          if (resourcePath != null) {
61              Map userSetting = loadAsMap(resourcePath);
62              defaultSetting.putAll(userSetting);
63          }
64          return defaultSetting;
65      }
66  
67      @SuppressWarnings("unchecked")
68      public Map loadAsMap(String path) throws IOException {
69          try {
70              String content = Resources.toString(Resources.getResource(path), Charset.forName("UTF-8"));
71              LOG.debug("Loaded resource file '{}'\n{}", path, content);
72              return loadStringAsMap(content);
73          } catch (IllegalArgumentException e) {
74              return new HashMap();
75          }
76      }
77  
78      @SuppressWarnings("unchecked")
79      public Map loadStringAsMap(String content) {
80          try {
81              Map settings = new Yaml().loadAs(content, Map.class);
82              return (settings != null) ? settings : new HashMap(0);
83          } catch (IllegalArgumentException e) {
84              return new HashMap();
85          }
86      }
87  
88  }