這是歷史版本頁面 — 看 Java Runtime Environment (64-bit) 最新版本
程式打不開一直說要裝 Java?JRE 是什麼、裝了能解決嗎
你剛從某個網站下載了一個軟體,雙擊安裝檔卻跳出錯誤視窗,說「需要 Java Runtime Environment」;或者你打開某個老牌網路銀行、公家機關系統,畫面一片空白,只有一行字叫你安裝 Java。你只是想趕快把事情辦完,卻卡在一個聽過名字、但從來不知道它是什麼的東西上。
你直覺的反應是上網搜尋 Java 下載,裝完卻發現問題沒解決,甚至跳出更多看不懂的錯誤訊息。這是因為這類工具不是一般應用程式,它是一個「執行環境」——負責讓用 Java 寫的程式在你的電腦上跑起來。裝錯版本、裝到開發工具、或沒注意系統位元數,都會讓你白忙一場。這篇文章要講清楚的,就是這個執行環境到底解決什麼問題、什麼時候你才真的需要它。
01Java Runtime Environment 到底是做什麼用的?裝了它能幹嘛?
它是一套讓 Java 程式能在你的 Windows 電腦上執行的必備元件,包含 Java 虛擬機(JVM)和一堆程式庫。白話來說,很多軟體、網頁元件、遊戲是用 Java 寫的,你的電腦沒有這套環境,那些程式就跑不起來。裝了之後,這些應用程式才能正常開啟,例如線上遊戲、3D 圖片檢視、某些企業內部系統。
02我怎麼知道電腦裡有沒有裝這套軟體?
打開命令提示字元(cmd),輸入 `java -version` 後按 Enter。如果有安裝,畫面上會顯示 Java 的版本資訊;如果顯示「不是內部或外部命令」之類的訊息,就代表沒裝。另外,也可以到 Windows 的「控制台 → 程式和功能」裡找有沒有 Java 相關的項目。
03這套軟體和 Java Development Kit(JDK)有什麼不同?
JRE 是拿來「執行」Java 程式的,JDK 是拿來「開發」Java 程式的。JDK 裡面包含了 JRE,但另外還有編譯器、除錯器等開發工具。如果你只是要跑別人寫好的 Java 軟體,裝 JRE 就夠了;如果你要自己寫 Java 程式,才需要裝 JDK。裝錯的話,只是佔用硬碟空間,不會造成系統問題。
04裝了這套軟體之後,還需要做什麼設定嗎?
一般情況下不需要。安裝完成後,Java 程式就能直接執行。不過,有些瀏覽器基於安全考量,預設會擋掉 Java 外掛,如果你需要透過瀏覽器使用 Java 應用程式(例如某些舊的網路銀行系統),可能要在瀏覽器的外掛管理或 Java 控制面板裡調整安全性設定,允許執行。
05這套軟體可以同時裝好幾個版本嗎?
可以。官方說明指出,你可以在同一台電腦上安裝多個版本的 JRE。不過,官方也建議只保留最新版本,因為舊版本可能含有未修補的安全性漏洞。如果你不確定某個舊版是不是還有程式在用,可以先保留,等確認沒問題後再移除。
06我只是想玩個遊戲或開個文書軟體,為什麼還要裝這個?
因為那個遊戲或軟體是用 Java 寫的。Java 的設計理念是「一次編寫,到處執行」,所以很多跨平台的應用程式會用它開發。開發者把程式包裝好之後,使用者的電腦必須有 JRE 才能把程式跑起來。這不是你的問題,而是軟體本身的技術需求。
07我的電腦是 64 位元的 Windows,該裝哪一個版本?
這套軟體名稱就標明是 64-bit,支援 Windows 7 到 Windows 11 的 64 位元系統。安裝前可以先確認你的 Windows 是 64 位元還是 32 位元(在「設定 → 系統 → 關於」裡可以查到)。如果你的系統是 32 位元,這套 64 位元版本就無法安裝,需要另外找 32 位元的版本。
08這套軟體的介面是英文的,我看不懂怎麼辦?
這套軟體的介面語系是英文,安裝過程和 Java 控制面板都是英文介面。不過,安裝完成後,你平常使用 Java 程式時並不會看到它的介面——它是在背景運作的。只有當你需要調整 Java 的安全性設定或更新時,才會需要面對英文介面。如果完全無法理解,可以找線上翻譯或請熟人協助。
09我裝了這套軟體之後,電腦變慢或出現安全警告,是正常的嗎?
Java 本身具備安全模型,包含沙箱(sandbox)、程式碼簽章和權限控管,目的是讓 Java 程式在受控的環境中執行。但因為 Java 曾多次被發現安全漏洞,所以有些防毒軟體或瀏覽器會對 Java 外掛發出警告。建議你只從官方網站下載,並保持軟體更新,以降低風險。
10我是一個程式設計師,裝這套軟體夠用嗎?
不夠。JRE 只能執行 Java 程式,不能編寫和編譯程式碼。如果你要開發 Java 應用程式,需要的是 JDK(Java Development Kit),它包含了編譯器(javac)和除錯工具。官方說明也明確指出,JDK 是用來開發的,JRE 是用來執行的。如果你只是要跑別人寫好的工具,JRE 就夠了。
11這套軟體一直叫我更新,不更新會怎樣?
官方建議定期更新,因為更新通常包含錯誤修正、安全性修補和效能改善。如果你不更新,舊版本可能無法執行某些新開發的 Java 程式,也可能暴露在已知的安全風險中。不過,更新與否最終取決於你使用的程式是否需要新版本——如果現有程式都跑得好好的,短期內不更新不會立刻出問題。
12有沒有其他軟體可以取代這套軟體?
如果你要執行 Java 程式,JRE 是必要的,沒有其他軟體可以完全取代它。資料中列出的相近軟體,例如 .NET Framework,是微軟開發的執行環境,用途不同,無法互相替代。如果你是要開發 Java 程式,可以考慮 NetBeans IDE 或 JDK,但這些是開發工具,不是執行環境。
下載與官方連結
前往官方網站 下載 Java Runtime Environment (64-bit)
jre-8u141-windows-x64.exe · 62.34 MB · 連結指向軟體原廠
版本紀錄
- 2026-10-21 Java JRE 8 Update 511 (64-bit) 75.31 MB
- 2026-08-19 Java JRE 8 Update 503 (64-bit) 69.02 MB
- 2026-07-22 Java JRE 8 Update 501 (64-bit) 69.02 MB
再看 5 筆
- 2026-04-22 Java JRE 8 Update 491 (64-bit) 69 MB
- 2026-01-21 Java JRE 8 Update 481 (64-bit) 38.5 MB
- 2025-10-22 Java JRE 8 Update 471 (64-bit) 38.48 MB
- 2025-07-16 Java JRE 8 Update 461 (64-bit) 38.48 MB
- 2025-04-16 Java JRE 8 Update 451 (64-bit) 38.41 MB
這一版改了什麼
What's new in this version:
IANA DATA 2017b:
- JDK 8u141 contains IANA time zone data version 2017b
CERTIFICATE CHANGES:
- Let's Encrypt certificates added to root CAs. One new root certificate has been added
NEW FEATURES:
security-libs/java.security. Improved algorithm constraints checking:
- With the need to restrict weak algorithms usage in situations where they are most vulnerable, additional features have been added when configuring the jdk.certpath.disabledAlgorithms and jdk.jar.disabledAlgorithms security properties in the java.security file.
- jdk.certpath.disabledAlgorithms: The certpath property has seen the most change. Previously it was limited to two Constraint types; either a full disabling of an algorithm by name or a full disabling of an algorithm by the key size when checking certificates, certificate chains, and certificate signatures. This creates configurations that are absolute and lack flexibility in their usage. Three new Constraints were added to give more flexibility in allowing and rejecting certificates.
- "jdkCA" examines the certificate chain termination with regard to the cacerts file. In the case of "SHA1 jdkCA". SHA1's usage is checked through the certificate chain, but the chain must terminate at a marked trust anchor in the cacerts keystore to be rejected. This is useful for organizations that have their own private CA that trust using SHA1 with their trust anchor, but want to block certificate chains anchored by a public CA from using SHA1.
- "denyAfter" checks if the given date is before the current date or the PKIXParameter date. In the case of "SHA1 denyAfter 2018-01-01", before 2018 a certificate with SHA1 can be used, but after that date, the certificate is rejected. This can be used for a policy across an organization that is phasing out an algorithm with a drop-dead date. For signed JAR files, the date is compared against the TSA timestamp. The date is specified in GMT.
"usage" examines the specified algorithm for a specified usage. This can be used when disabling an algorithm for all usages is not practical. There are three usages that can be specified:
- TLSServer' restricts the algorithm in TLS server certificate chains when server authentication is performed as a client
- TLSClient' restricts the algorithm in TLS client certificate chains when client authentication is performed as a server
- SignedJAR' restricts the algorithms in certificates in signed JAR files. The usage type follows the keyword and more than one usage type can be specified with a whitespace delimiter
- For example, "SHA1 usage TLSServer TLSClient" would disallow SHA1 certificates for TLSServer and TLSClient operations, but SignedJars would be allowed
- All of these constraints can be combined to constrain an algorithm when delimited by '&'. For example, to disable SHA1 certificate chains that terminate at marked trust anchors only for TLSServer operations, the constraint would be "SHA1 jdkCA & usage TLSServer"
- jdk.jar.disabledAlgorithms: One additional constraint was added to this .jar property to restrict JAR manifest algorithms
- "denyAfter" checks algorithm constraints on manifest digest algorithms inside a signed JAR file. The date given in the constraint is compared against the TSA timestamp on the signed JAR file. If there is no timestamp or the timestamp is on or after the specified date, the signed JAR file is treated as unsigned. If the timestamp is before the specified date, the .jar will operate as a signed JAR file. The syntax for restricting SHA1 in JAR files signed after January 1st 2018 is: "SHA1 denyAfter 2018-01-01". The syntax is the same as that for the certpath property, however certificate checking will not be performed by this property
CHANGES:
core-svc/java.lang.management. JMX Diagnostic improvements:
- com.sun.management.HotSpotDiagnostic::dumpHeap API is modified to throw IllegalArgumentException if the supplied file name does not end with “.hprof” suffix. Existing applications which do not provide a file name ending with the “.hprof” extension will fail with IllegalArgumentException. In that case, applications can either choose to handle the exception or restore old behavior by setting system property 'jdk.management.heapdump.allowAnyFileSuffix' to true.
security-libs/javax.net.ssl. Custom HostnameVerifier enables SNI extension:
- Earlier releases of JDK 8 Updates didn't always send the Server Name Indication (SNI) extension in the TLS ClientHello phase if a custom hostname verifier was used. This verifier is set via the setHostnameVerifier(HostnameVerifier v) method in HttpsURLConnection. The fix ensures the Server Name is now sent in the ClientHello body.
xml/jax-ws. Tighter secure checks on processing WSDL files by wsimport tool:
The wsimport tool has been changed to disallow DTDs in Web Service descriptions, specifically:
- DOCTYPE declaration is disallowed in documents
- External general entities are not included by default
- External parameter entities are not included by default
- External DTDs are completely ignored
To restore the previous behavior:
- Set the System property com.sun.xml.internal.ws.disableXmlSecurity to true
- Use the wsimport tool command line option –disableXmlSecurity
- NOTE: JDK 7 and JDK 6 support for this option in wsimport will be provided via a Patch release post July CPU
BUG FIXES:
- JFileChooser with Windows look and feel crashes on win 10
- Race Condition in java.lang.reflect.WeakCache
- java.nio.Bits.unaligned() doesn't return true on ppc
- After updating to Java8u131, the bind to rmiregistry is rejected by registryFilter even though registryFilter is set
- sun.management.LazyCompositeData.isTypeMatched() fail for composite types with items of ArrayType
- SafePointNode::_replaced_nodes breaks with irreducible loops
- NPE when JavaFX loads default stylesheet or font families if CCL is null
- WebEngine.getDocument().getDocumentURI() no longer returns null for loading a String of HTML
- Failed to load RSA private key from pkcs12
- Improved algorithm constraints checking
- Custom HostnameVerifier disables SNI extension