{"id":826,"date":"2012-11-29T12:00:22","date_gmt":"2012-11-29T03:00:22","guid":{"rendered":"http:\/\/www.techscore.com\/blog\/?p=826"},"modified":"2018-11-14T16:33:59","modified_gmt":"2018-11-14T07:33:59","slug":"%e6%96%87%e5%ad%97%e5%88%97%e7%b5%90%e5%90%88-java%e7%b7%a8","status":"publish","type":"post","link":"https:\/\/www.techscore.com\/blog\/2012\/11\/29\/%e6%96%87%e5%ad%97%e5%88%97%e7%b5%90%e5%90%88-java%e7%b7%a8\/","title":{"rendered":"\u3042\u3048\u3066\u8a00\u3046\u307b\u3069\u3067\u306f\u306a\u3044 \u6587\u5b57\u5217\u7d50\u5408 Java\u7de8"},"content":{"rendered":"

\u3053\u3093\u306b\u3061\u306f
\n\u5f15\u304d\u7d9a\u304d\u5143Java\u30d7\u30ed\u30b0\u30e9\u30de\u30fc\u6751\u4e0a\u3067\u3059\u3002<\/p>\n

\u524d\u56de\u306f\u6587\u5b57\u5217\u21d4\u6570\u5024\u306e\u5909\u63db\u30b3\u30b9\u30c8\u306b\u3064\u3044\u3066\u66f8\u304b\u305b\u3066\u3082\u3089\u3044\u307e\u3057\u305f\u304c\u3001
\n\u4eca\u56de\u306f\u6587\u5b57\u5217\u7d50\u5408\u306b\u3064\u3044\u3066\u305d\u306e\u52b9\u7387\u6027\u3092\u691c\u8a3c\u3057\u3066\u307f\u3088\u3046\u304b\u306a\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n

Java\u306b\u304a\u3051\u308b\u6587\u5b57\u5217\u7d50\u5408\u306f\u6b21\u306e4\u3064\u306e\u65b9\u6cd5\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n

\u30d7\u30e9\u30b9\u6f14\u7b97\u5b50<\/h3>\n
String s1 = \"aaa\";\r\nString s2 = \"bbb\";\r\nString s = s1 + s2;<\/pre>\n
String#concat()<\/h3>\n
String s1 = \"aaa\";\r\nString s2 = \"bbb\";\r\nString s = s1.concat(s2);<\/pre>\n
StringBuffer<\/h3>\n
String s1 = \"aaa\";\r\nString s2 = \"bbb\";\r\nStringBufferbuf = new StringBuffer();\r\nbuf.append(s1);\r\nbuf.append(s2);\r\nString s = buf.toString();<\/pre>\n
StringBuilder<\/h3>\n
String s1 = \"aaa\";\r\nString s2 = \"bbb\";\r\nStringBuilder buf = new StringBuilder();\r\nbuf.append(s1);\r\nbuf.append(s2);\r\nString s = buf.toString();<\/pre>\n
\u63a8\u5968\u306f\u300cStringBuffer\u300d\u304b\u300cStringBuilder\u300d\u3067\u3057\u3087\u3046\u3002<\/p>\n
\u4eca\u56de\u306f\u30eb\u30fc\u30d7\u51e6\u7406\u3067\u6587\u5b57\u5217\u3092\u7d50\u5408\u3059\u308b\u6642\u306e\u6642\u9593\u3092\u6e2c\u3063\u3066\u307f\u307e\u3059\u3002
\n\u30b3\u30fc\u30c9\u306f\u3053\u3093\u306a\u611f\u3058\u3067<\/p>\n
String str = \"\";\r\nfor (int i = 0; i < LOOP_COUNT; i++) {\r\n\tstr = str + \"hoge\";\r\n}<\/pre>\n
\u5358\u4f4d\u306f\u30df\u30ea\u79d2\u3067\u3059\u3002<\/p>\n\n\n\n\n\n\n\n
\u30eb\u30fc\u30d7100000\u56de<\/th>\nJava5<\/th>\nJava6<\/th>\nJava7<\/th>\n<\/tr>\n
\u30d7\u30e9\u30b9\u6f14\u7b97\u5b50<\/td>\n\u6e2c\u5b9a\u4e0d\u80fd<\/td>\n20616<\/td>\n15989<\/td>\n<\/tr>\n
String#concat()<\/td>\n\u6e2c\u5b9a\u4e0d\u80fd<\/td>\n10105<\/td>\n7987<\/td>\n<\/tr>\n
StringBuffer<\/td>\n11<\/td>\n2<\/td>\n2<\/td>\n<\/tr>\n
StringBuilder<\/td>\n9<\/td>\n2<\/td>\n1<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\u51e6\u7406\u6642\u9593\u306e\u9806\u4f4d\u306f\u4e88\u60f3\u3069\u304a\u308a\u3067\u3059\u304c\u3001\u51e6\u7406\u6642\u9593\u306f\u30e1\u30c3\u30c1\u30e3\u5dee\u304c\u4ed8\u304d\u307e\u3057\u305f\u306d\u3002
\n\u3084\u3063\u3071\u308a\u63a8\u5968\u3055\u308c\u3066\u3044\u308b\u3082\u306e\u3092\u4f7f\u3046\u3079\u304d\u3067\u3059\u3002<\/p>\n
\u3061\u306a\u307f\u306b\u30eb\u30fc\u30d7\u56de\u6570\u3067\u3059\u304c\u300110\u4e07\u56de\u3092100\u4e07\u56de\u306b\u3059\u308b\u3068Java5\u30686\u306fOutOfMemory\u3067\u3057\u305f\u304c\u3001\u540c\u3058\u30e1\u30e2\u30ea\u5bb9\u91cf\u3067Java7\u306f1000\u4e07\u56de\u3067\u3082\u52d5\u4f5c\u3057\u307e\u3057\u305f\u3002
\nJava\u306e\u9032\u5316\u306f\u3059\u3054\u3044\uff01\uff01<\/p>\n
\u691c\u8a3c\u306f\u30eb\u30fc\u30d7\u5185\u3067\u6587\u5b57\u5217\u3092\u7d50\u5408\u3057\u3066\u3044\u304f\u30b3\u30fc\u30c9\u306b\u3057\u307e\u3057\u305f\u304c\u3001\u5358\u7d14\u306a\u6587\u5b57\u5217\u7d50\u5408\u306e\u5834\u5408\u306f\u3069\u3046\u306a\u308b\u304b\u3082\u691c\u8a3c\u3057\u3066\u307f\u307e\u3057\u305f\u3002
\n\u30b3\u30fc\u30c9\u306f\u3053\u3093\u306a\u611f\u3058\u3067\u3059\u3002<\/p>\n
\u30d7\u30e9\u30b9\u6f14\u7b97\u5b50<\/h3>\n
for (int i = 0; i < LOOP_COUNT; i++) {\r\n\tString s1 = \"aaa\";\r\n\tString s2 = \"bbb\";\r\n\tString s = s1 + s2;\r\n}<\/pre>\n
StringBuffer<\/h3>\n
for (int i = 0; i < LOOP_COUNT; i++) {\r\n\tString s1 = \"aaa\";\r\n\tString s2 = \"bbb\";\r\n\tStringBufferbuf = new StringBuffer();\r\n\tbuf.append(s1);\r\n\tbuf.append(s2);\r\n\tString s = buf.toString();\r\n}<\/pre>\n
\u691c\u8a3c\u30b3\u30fc\u30c9\u306f\u7d50\u5408\u3059\u308b\u6587\u5b57\u3092200\u6587\u5b57\u3050\u3089\u3044\u306b\u5897\u3084\u3057\u3066\u307e\u3059\u3002
\n\u7d50\u679c\u306f\u4e0b\u8a18\u306e\u901a\u308a
\n\u5358\u4f4d\u306f\u30df\u30ea\u79d2\u3067\u3059\u3002<\/p>\n\n\n\n\n\n\n
\u30eb\u30fc\u30d7100000\u56de<\/th>\nJava5<\/th>\nJava6<\/th>\nJava7<\/th>\n<\/tr>\n
\u30d7\u30e9\u30b9\u6f14\u7b97\u5b50<\/td>\n467<\/td>\n353<\/td>\n286<\/td>\n<\/tr>\n
StringBuffer<\/td>\n744<\/td>\n445<\/td>\n493<\/td>\n<\/tr>\n
StringBuilder<\/td>\n462<\/td>\n351<\/td>\n282<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
String\u306e\u30d7\u30e9\u30b9\u6f14\u7b97\u5b50\u306f\u88cf\u3067\u306fStringBuilder\u3067\u6587\u5b57\u5217\u7d50\u5408\u3057\u3066\u308b\u307f\u305f\u3044\u306a\u306e\u3067\u3001\u30d7\u30e9\u30b9\u6f14\u7b97\u5b50\u3068StringBuffer\u3067\u306f\u30d7\u30e9\u30b9\u6f14\u7b97\u5b50\u306e\u65b9\u304c\u901f\u304f\u306a\u308b\u3093\u3067\u3059\u306d\u3002
\n\u4e00\u884c\u3067\u6587\u5b57\u5217\u7d50\u5408\u3059\u308b\u5834\u5408\u306f\u30d7\u30e9\u30b9\u6f14\u7b97\u5b50\u3092\u4f7f\u7528\u3057\u3066\u3082\u554f\u984c\u7121\u3044\u6c17\u304c\u3057\u307e\u3059\u306d\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u3053\u3093\u306b\u3061\u306f
\n\u5f15\u304d\u7d9a\u304d\u5143Java\u30d7\u30ed\u30b0\u30e9\u30de\u30fc\u6751\u4e0a\u3067\u3059\u3002<\/p>\n
\u524d\u56de\u306f\u6587\u5b57\u5217\u21d4\u6570\u5024\u306e\u5909\u63db\u30b3\u30b9\u30c8\u306b\u3064\u3044\u3066\u66f8\u304b\u305b\u3066\u3082\u3089\u3044\u307e\u3057\u305f\u304c\u3001
\n\u4eca\u56de\u306f\u6587\u5b57\u5217\u7d50\u5408\u306b\u3064\u3044\u3066\u305d\u306e\u52b9\u7387\u6027\u3092\u691c\u8a3c\u3057\u3066\u307f\u3088\u3046\u304b\u306a\u3068\u601d\u3044\u307e\u3059\u3002
\u7d9a\u304d\u3092\u8aad\u3080...<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[18],"tags":[57,28],"_links":{"self":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/826"}],"collection":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/comments?post=826"}],"version-history":[{"count":2,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/826\/revisions"}],"predecessor-version":[{"id":20058,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/posts\/826\/revisions\/20058"}],"wp:attachment":[{"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/media?parent=826"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/categories?post=826"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.techscore.com\/blog\/wp-json\/wp\/v2\/tags?post=826"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}