{"id":1063,"date":"2022-12-15T18:46:43","date_gmt":"2022-12-15T09:46:43","guid":{"rendered":"https:\/\/java.ihavenomoney.co.kr\/?page_id=1063"},"modified":"2022-12-15T18:55:48","modified_gmt":"2022-12-15T09:55:48","slug":"map-hashmap","status":"publish","type":"page","link":"https:\/\/java.ihavenomoney.co.kr\/?page_id=1063","title":{"rendered":"Map, HashMap"},"content":{"rendered":"\n

Remark : \uc778\ud130\ud398\uc774\uc2a4 Map \uc774\ub77c \uc544\ub798\uc640 \uac19\uc774 \uc0ac\uc6a9<\/p>\n\n\n\n

Map<String, Object> map = new HashMap<>(); \/\/\uc778\ud130\ud398\uc774\uc2a4 Map <\/pre><\/div>\n\n\n\n
package com.example.demo;\n\nimport org.apache.catalina.LifecycleException;\nimport org.json.simple.JSONObject;\nimport org.springframework.boot.autoconfigure.SpringBootApplication;\nimport java.io.IOException;\nimport java.util.*;\n\n@SpringBootApplication\npublic class DemoApplication {\n\n    public static void main(String[] args) throws IOException, LifecycleException {\n\n        \/\/SpringApplication.run(DemoApplication.class, args);\n\n        DemoApplication demo = new DemoApplication();\n        demo.emit();\n    }\n    public void emit() {\n\n        Map<String, Object> map = new HashMap<>(); \/\/\uc778\ud130\ud398\uc774\uc2a4 Map\n        map.put(\"key1\", \"value01\");\n        map.put(\"key2\", 2);\n        map.put(\"key3\", \"value03\");\n\n        \/\/ \uc800\uc7a5\ud55c \ub370\uc774\ud130 \uaebc\ub0b4\uc624\uae30\n        System.out.println(\"key \ucd9c\ub825>>>\" + map.keySet()); \/\/ key \ucd9c\ub825>>>[key1, key2, key3]\n        System.out.println(\"value \ucd9c\ub825>>>\" + map.values()); \/\/ value \ucd9c\ub825>>>[value01, 2, value03]\n        System.out.println(\"key value \ucd9c\ub825>>>\" + map.toString()); \/\/ key value \ucd9c\ub825>>>{key1=value01, key2=2, key3=value03}\n        System.out.println(\"\ud574\ub2f9\ud0a4\uc758 \uac12\uc744 \ucd9c\ub825>>>\" + map.get(\"key3\")); \/\/ \ud574\ub2f9\ud0a4\uc758 \uac12\uc744 \ucd9c\ub825>>>value03\n\n        \/\/ \ub370\uc774\ud130 \uc0ad\uc81c\ud558\uae30\n        map.remove(\"key2\");\n\n        \/\/ \ub370\uc774\ud130 \uc218\uc815\ud558\uae30\n        map.replace(\"key3\", \"value33\");\n\n        Map<String, String> map2 = new HashMap<String, String>();\n        map2.put(\"k1\", \"valuek1\");\n        map2.put(\"k2\", \"valuek2\");\n        map2.put(\"k3\", \"valuek3\");\n        map2.put(\"k3\", \"valuek33\"); \/\/ \uc911\ubcf5\ub418\ub294 \ud0a4 \uac12\uc911 \ub9c8\uc9c0\ub9c9 \ub370\uc774\ud130\uac00 \ub36e\uc5b4\uc500\n\n        Collection<String> col = map2.values(); \/\/Collection\n        Iterator<String> it = col.iterator(); \/\/Iterator\n\n        System.out.println(\"<< \uc804\uccb4 map2\ub370\uc774\ud130 >>\");\n        while (it.hasNext()) {\n            System.out.println(it.next());\n        }\n\n        System.out.println(\"<< \uc804\uccb4 map2\uc758 \ud0a4 \ucd9c\ub825 >>\");\n        Set<String> set = map2.keySet();\n        Iterator<String> keyset = set.iterator();\n        while (keyset.hasNext()) {\n            String key = keyset.next();\n            System.out.println(key + \"\uc5d0 \uc800\uc7a5\ub41c \ub370\uc774\ud130 :\" + map2.get(key));\n        }\n        System.out.println(\"=====================\");\n    }\n}<\/pre><\/div>\n\n\n\n
key \ucd9c\ub825>>>[key1, key2, key3]\nvalue \ucd9c\ub825>>>[value01, 2, value03]\nkey value \ucd9c\ub825>>>{key1=value01, key2=2, key3=value03}\n\ud574\ub2f9\ud0a4\uc758 \uac12\uc744 \ucd9c\ub825>>>value03\n<< \uc804\uccb4 map2\ub370\uc774\ud130 >>\nvaluek1\nvaluek2\nvaluek33\n<< \uc804\uccb4 map2\uc758 \ud0a4 \ucd9c\ub825 >>\nk1\uc5d0 \uc800\uc7a5\ub41c \ub370\uc774\ud130 :valuek1\nk2\uc5d0 \uc800\uc7a5\ub41c \ub370\uc774\ud130 :valuek2\nk3\uc5d0 \uc800\uc7a5\ub41c \ub370\uc774\ud130 :valuek33\n=====================<\/pre><\/div>\n","protected":false},"excerpt":{"rendered":"
Remark : \uc778\ud130\ud398\uc774\uc2a4 Map \uc774\ub77c \uc544\ub798\uc640 \uac19\uc774 \uc0ac\uc6a9<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1063","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/java.ihavenomoney.co.kr\/index.php?rest_route=\/wp\/v2\/pages\/1063","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/java.ihavenomoney.co.kr\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/java.ihavenomoney.co.kr\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/java.ihavenomoney.co.kr\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/java.ihavenomoney.co.kr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1063"}],"version-history":[{"count":2,"href":"https:\/\/java.ihavenomoney.co.kr\/index.php?rest_route=\/wp\/v2\/pages\/1063\/revisions"}],"predecessor-version":[{"id":1066,"href":"https:\/\/java.ihavenomoney.co.kr\/index.php?rest_route=\/wp\/v2\/pages\/1063\/revisions\/1066"}],"wp:attachment":[{"href":"https:\/\/java.ihavenomoney.co.kr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1063"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}