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zhuhjay 22e48d9558 build(www): 添加 Drone CI 流水线配置 
- 新增 .drone.yml 文件用于定义 CI/CD 流程
- 配置了基于 Docker 的部署步骤
- 设置了工作区和卷映射以支持持久化数据
- 添加了构建准备阶段和 Docker 部署阶段
- 定义了环境变量和代理设置
- 配置了 artifacts 目录的处理逻辑
- 添加了 timezone 映射以确保时间同步
- 设置了 docker.sock 映射以支持 Docker in Docker
2025-11-01 13:36:00 +08:00

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"),t("li",[s._v("Stream并行处理的过程会分而治之，也就是将一个大任务切分成多个小任务，这表示每个任务都是一个操作。")])]),s._v(" "),t("h4",{attrs:{id:"parallelstream线程安全问题"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#parallelstream线程安全问题"}},[s._v("#")]),s._v(" ParallelStream线程安全问题")]),s._v(" "),t("div",{staticClass:"language-java line-numbers-mode"},[t("pre",{pre:!0,attrs:{class:"language-java"}},[t("code",[t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("public")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("class")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token class-name"}},[s._v("StreamParallelTest")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("{")]),s._v("\n "),t("span",{pre:!0,attrs:{class:"token annotation punctuation"}},[s._v("@Test")]),s._v("\n "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("public")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("void")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token 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punctuation"}},[s._v(")")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("{")]),s._v("\n "),t("span",{pre:!0,attrs:{class:"token comment"}},[s._v("// 任务不用再拆分了.可以计算了")]),s._v("\n "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("long")]),s._v(" sum "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("=")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token number"}},[s._v("0")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(";")]),s._v("\n "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("for")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("(")]),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("long")]),s._v(" i "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("=")]),s._v(" start"),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(";")]),s._v(" i "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("<=")]),s._v(" end"),t("span",{pre:!0,attrs:{class:"token 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keyword"}},[s._v("long")]),s._v(" middle "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("=")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("(")]),s._v("start "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("+")]),s._v(" end"),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(")")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("/")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token number"}},[s._v("2")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(";")]),s._v("\n\n "),t("span",{pre:!0,attrs:{class:"token class-name"}},[s._v("SumRecursiveTask")]),s._v(" left "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("=")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("new")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token class-name"}},[s._v("SumRecursiveTask")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("(")]),s._v("start"),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(",")]),s._v(" middle"),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(")")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(";")]),s._v("\n left"),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(".")]),t("span",{pre:!0,attrs:{class:"token function"}},[s._v("fork")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("(")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(")")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(";")]),s._v("\n "),t("span",{pre:!0,attrs:{class:"token class-name"}},[s._v("SumRecursiveTask")]),s._v(" right "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("=")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("new")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token class-name"}},[s._v("SumRecursiveTask")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("(")]),s._v("middle "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("+")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token number"}},[s._v("1")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(",")]),s._v(" end"),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(")")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(";")]),s._v("\n right"),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(".")]),t("span",{pre:!0,attrs:{class:"token function"}},[s._v("fork")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("(")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(")")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(";")]),s._v("\n "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("return")]),s._v(" left"),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(".")]),t("span",{pre:!0,attrs:{class:"token function"}},[s._v("join")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("(")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(")")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("+")]),s._v(" right"),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(".")]),t("span",{pre:!0,attrs:{class:"token function"}},[s._v("join")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("(")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(")")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(";")]),s._v("\n "),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("}")]),s._v("\n "),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("}")]),s._v("\n"),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("}")]),s._v("\n")])]),s._v(" "),t("div",{staticClass:"line-numbers-wrapper"},[t("span",{staticClass:"line-number"},[s._v("1")]),t("br"),t("span",{staticClass:"line-number"},[s._v("2")]),t("br"),t("span",{staticClass:"line-number"},[s._v("3")]),t("br"),t("span",{staticClass:"line-number"},[s._v("4")]),t("br"),t("span",{staticClass:"line-number"},[s._v("5")]),t("br"),t("span",{staticClass:"line-number"},[s._v("6")]),t("br"),t("span",{staticClass:"line-number"},[s._v("7")]),t("br"),t("span",{staticClass:"line-number"},[s._v("8")]),t("br"),t("span",{staticClass:"line-number"},[s._v("9")]),t("br"),t("span",{staticClass:"line-number"},[s._v("10")]),t("br"),t("span",{staticClass:"line-number"},[s._v("11")]),t("br"),t("span",{staticClass:"line-number"},[s._v("12")]),t("br"),t("span",{staticClass:"line-number"},[s._v("13")]),t("br"),t("span",{staticClass:"line-number"},[s._v("14")]),t("br"),t("span",{staticClass:"line-number"},[s._v("15")]),t("br"),t("span",{staticClass:"line-number"},[s._v("16")]),t("br"),t("span",{staticClass:"line-number"},[s._v("17")]),t("br"),t("span",{staticClass:"line-number"},[s._v("18")]),t("br"),t("span",{staticClass:"line-number"},[s._v("19")]),t("br"),t("span",{staticClass:"line-number"},[s._v("20")]),t("br"),t("span",{staticClass:"line-number"},[s._v("21")]),t("br"),t("span",{staticClass:"line-number"},[s._v("22")]),t("br"),t("span",{staticClass:"line-number"},[s._v("23")]),t("br"),t("span",{staticClass:"line-number"},[s._v("24")]),t("br"),t("span",{staticClass:"line-number"},[s._v("25")]),t("br"),t("span",{staticClass:"line-number"},[s._v("26")]),t("br"),t("span",{staticClass:"line-number"},[s._v("27")]),t("br"),t("span",{staticClass:"line-number"},[s._v("28")]),t("br"),t("span",{staticClass:"line-number"},[s._v("29")]),t("br"),t("span",{staticClass:"line-number"},[s._v("30")]),t("br"),t("span",{staticClass:"line-number"},[s._v("31")]),t("br"),t("span",{staticClass:"line-number"},[s._v("32")]),t("br"),t("span",{staticClass:"line-number"},[s._v("33")]),t("br"),t("span",{staticClass:"line-number"},[s._v("34")]),t("br"),t("span",{staticClass:"line-number"},[s._v("35")]),t("br"),t("span",{staticClass:"line-number"},[s._v("36")]),t("br"),t("span",{staticClass:"line-number"},[s._v("37")]),t("br"),t("span",{staticClass:"line-number"},[s._v("38")]),t("br"),t("span",{staticClass:"line-number"},[s._v("39")]),t("br"),t("span",{staticClass:"line-number"},[s._v("40")]),t("br"),t("span",{staticClass:"line-number"},[s._v("41")]),t("br"),t("span",{staticClass:"line-number"},[s._v("42")]),t("br"),t("span",{staticClass:"line-number"},[s._v("43")]),t("br"),t("span",{staticClass:"line-number"},[s._v("44")]),t("br"),t("span",{staticClass:"line-number"},[s._v("45")]),t("br"),t("span",{staticClass:"line-number"},[s._v("46")]),t("br"),t("span",{staticClass:"line-number"},[s._v("47")]),t("br"),t("span",{staticClass:"line-number"},[s._v("48")]),t("br"),t("span",{staticClass:"line-number"},[s._v("49")]),t("br")])]),t("h3",{attrs:{id:"_1-9-小结"}},[t("a",{staticClass:"header-anchor",attrs:{href:"#_1-9-小结"}},[s._v("#")]),s._v(" 1.9 小结")]),s._v(" "),t("ol",[t("li",[s._v("parallelStream是线程不安全的")]),s._v(" "),t("li",[s._v("parallelStream适用的场景是CPU密集型的，只是做到别浪费CPU，假如本身电脑CPU的负载很大，那还到处用并行流，那并不能起到作用")]),s._v(" "),t("li",[s._v("I/O密集型磁盘I/O、网络I/O都属于I/O操作，这部分操作是较少消耗CPU资源，一般并行流中不适用于I/O密集型的操作，就比如使用并流行进行大批量的消息推送，涉及到了大量I/O，使用并行流反而慢了很多")]),s._v(" "),t("li",[s._v("在使用并行流的时候是无法保证元素的顺序的，也就是即使你用了同步集合也只能保证元素都正确但无法保证其中的顺序")])])])}),[],!1,null,null,null);t.default=e.exports}}]);
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