java list 按属性分组_java List按照对象的属性进行分组

刺骨的言语ヽ痛彻心扉 2022-11-02 15:30 339阅读 0赞

1 //

2 // 分组 返回Map3 //4

6 packagecom.xxxx.dsc.application.utils;7

8 importjava.util.ArrayList;9 importjava.util.HashMap;10 importjava.util.HashSet;11 importjava.util.LinkedHashMap;12 importjava.util.List;13 importjava.util.Set;14 importorg.apache.commons.collections.CollectionUtils;15

16 public classHashlize \{17 publicHashlize() \{18 \}19

20 public staticHashMap hashlizeObjects(Object\[\] objs, IHashKey iHashKey) \{21 if (objs != null && objs.length != 0) \{22 if (iHashKey == null) \{23 throw new RuntimeException("iHashKey cann't be null");24 \} else\{25 HashMap result = newHashMap();26

27 for(int i = 0; i < objs.length; ++i) \{28 String key =iHashKey.getKey(objs\[i\]);29 ArrayList al =(ArrayList)result.get(key);30 if (al == null) \{31 al = newArrayList();32 result.put(key, al);33 \}34

35 al.add(objs\[i\]);36 \}37

38 returnresult;39 \}40 \} else\{41 return null;42 \}43 \}44

45 public staticHashMap hashlizeObjects(List objs, IHashKey iHashKey) \{46 if (objs != null && !objs.isEmpty()) \{47 if (iHashKey == null) \{48 throw new RuntimeException("iHashKey cann't be null");49 \} else\{50 HashMap result = newHashMap();51

52 for(int i = 0; i < objs.size(); ++i) \{53 String key =iHashKey.getKey(objs.get(i));54 ArrayList al =(ArrayList)result.get(key);55 if (al == null) \{56 al = newArrayList();57 result.put(key, al);58 \}59

60 al.add(objs.get(i));61 \}62

63 returnresult;64 \}65 \} else\{66 return null;67 \}68 \}69

70 public staticLinkedHashMap hashlizeObjectsLinked(List objs, IHashKey iHashKey) \{71 if (objs != null && !objs.isEmpty()) \{72 if (iHashKey == null) \{73 throw new RuntimeException("iHashKey cann't be null");74 \} else\{75 LinkedHashMap result = newLinkedHashMap();76

77 for(int i = 0; i < objs.size(); ++i) \{78 String key =iHashKey.getKey(objs.get(i));79 ArrayList al =(ArrayList)result.get(key);80 if (al == null) \{81 al = newArrayList();82 result.put(key, al);83 \}84

85 al.add(objs.get(i));86 \}87

88 returnresult;89 \}90 \} else\{91 return null;92 \}93 \}94

95 public staticHashMap hashlizeMap(Object\[\] objs, IHashKey iHashKey) \{96 if (objs != null && objs.length != 0) \{97 if (iHashKey == null) \{98 throw new RuntimeException("iHashKey cann't be null");99 \} else\{100 HashMap result = newHashMap();101

102 for(int i = 0; i < objs.length; ++i) \{103 String key =iHashKey.getKey(objs\[i\]);104 result.put(key, objs\[i\]);105 \}106

107 returnresult;108 \}109 \} else\{110 return null;111 \}112 \}113

114 public staticHashMap hashlizeMap(List objs, IHashKey iHashKey) \{115 if (objs != null && !objs.isEmpty()) \{116 if (iHashKey == null) \{117 throw new RuntimeException("iHashKey cann't be null");118 \} else\{119 HashMap result = newHashMap();120

121 for(int i = 0; i < objs.size(); ++i) \{122 String key =iHashKey.getKey(objs.get(i));123 result.put(key, objs.get(i));124 \}125

126 returnresult;127 \}128 \} else\{129 return null;130 \}131 \}132

133 public staticHashMap hashlizeObjects(Object\[\] objs, IHashKey iHashKey, ICombine iCombine) \{134 if (objs != null && objs.length != 0) \{135 if (iHashKey == null) \{136 throw new RuntimeException("iHashKey cann't be null");137 \} else\{138 HashMap result = newHashMap();139

140 for(int i = 0; i < objs.length; ++i) \{141 String key =iHashKey.getKey(objs\[i\]);142 Object o =result.get(key);143 result.put(key, iCombine.combine(o, objs\[i\]));144 \}145

146 returnresult;147 \}148 \} else\{149 return null;150 \}151 \}152

153 public staticHashMap hashlizeObjects(List objs, IHashKey iHashKey, ICombine iCombine) \{154 if (objs != null && !objs.isEmpty()) \{155 if (iHashKey == null) \{156 throw new RuntimeException("iHashKey cann't be null");157 \} else\{158 HashMap result = newHashMap();159 int size =objs.size();160

161 for(int i = 0; i < size; ++i) \{162 String key =iHashKey.getKey(objs.get(i));163 Object o =result.get(key);164 result.put(key, iCombine.combine(o, objs.get(i)));165 \}166

167 returnresult;168 \}169 \} else\{170 return null;171 \}172 \}173

174 public staticLinkedHashMap linkedHashlizeObjects(List objs, IHashKey iHashKey, ICombine iCombine) \{175 if (objs != null && !objs.isEmpty()) \{176 if (iHashKey == null) \{177 throw new RuntimeException("iHashKey cann't be null");178 \} else\{179 LinkedHashMap result = newLinkedHashMap();180 int size =objs.size();181

182 for(int i = 0; i < size; ++i) \{183 String key =iHashKey.getKey(objs.get(i));184 Object o =result.get(key);185 result.put(key, iCombine.combine(o, objs.get(i)));186 \}187

188 returnresult;189 \}190 \} else\{191 return null;192 \}193 \}194

195 public static SethashlizeSet(List objs, IHashKey iHashKey) \{196 if(CollectionUtils.isEmpty(objs)) \{197 return null;198 \} else if (iHashKey == null) \{199 throw new RuntimeException("iHashKey cann't be null");200 \} else\{201 Set result = newHashSet();202

203 for(int i = 0; i < objs.size(); ++i) \{204 String key =iHashKey.getKey(objs.get(i));205 result.add(key);206 \}207

208 returnresult;209 \}210 \}211

212 public static ListhashlizeList(List objs, IHashKey iHashKey) \{213 if(CollectionUtils.isEmpty(objs)) \{214 return null;215 \} else if (iHashKey == null) \{216 throw new RuntimeException("iHashKey cann't be null");217 \} else\{218 List result = newArrayList();219

220 for(int i = 0; i < objs.size(); ++i) \{221 String key =iHashKey.getKey(objs.get(i));222 result.add(key);223 \}224

225 returnresult;226 \}227 \}228 \}