This page describes the patch-in-place and static installation types.
The page contains these topics:
This information applies to Java SE Runtime Environment (JRE) installers running on Microsoft Windows. See "JDK 8 and JRE 8 Installation Start Here" for general information about installing JDK 8 and JRE 8.
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Note: This page may refer to versions of the JRE that do not exist; these versions are used to demonstrate the concepts of patch-in-place and static JRE installations. |
In the past, when a user installed different versions of the JRE, the user would be left with multiple installation directories and several entries in the Add/Remove Programs dialog in the Control Panel. This resulted in unnecessary proliferation of unused JREs.
The JRE can now be installed in two configurations: patch-in-place and static. JRE updates can be configured to patch an existing installation or to do a brand new installation.
The JRE may be installed in silent (non-interactive) or nonsilent (interactive) modes. For more information on silent install and uninstalling a silent installation, see "Command-Line Installation".
The patch-in-place mode implies that when a version of the JRE exists on a machine, any updates belonging to the same JRE family will be done in place, meaning, the existing JRE will be patched with changes. A JRE is installed in patch-in-place mode by default. The default installation directory of a patch-in-place installation is C:\Program Files\Java\jren, where n is the Java SE minor version number.
For example, if a user previously installed JRE 8 Update 1 in the default directory C:\Program Files\Java\jre8, and now attempts to install JRE 8 Update 3, the JRE 8 Update 3 installer does not create a new directory. Instead, it updates the preexisting C:\Program Files\Java\jre8 directory with the new 8 Update 3 content. The user is left with JRE 8 Update 3 only. JRE 8 Update 1 no longer exists.
When a JRE is installed in static mode, it will not be updated in place by later versions. A later version from the same JRE family will be installed in a separate directory. This mode ensures that vendors who require a specific version of the JRE for their product can be certain that the JRE will not be overwritten by a later version.
Some of the characteristics of a static JRE installation are as follows:
A static JRE installation (for example, 8 Update 15) will ignore a previous patch-in-place installation of another JRE (for example, 8 Update 10)
A static JRE installation is never overwritten by another JRE version
When a newer JRE version is present (for example, 8 Update 15), older JRE versions (for example, 8 Update 12) are installed in static mode only
A patch-in-place JRE can be overwritten by a static JRE installation of the same version. The user will be left with one static JRE installation.
The default installation directory of a static JRE is C:\Program Files\Java\jreversion. For example, by default, a static JRE 8 Update 10 will be installed in the directory C:\Program Files\Java\jre1.8.0_10.
To perform a static JRE installation, use the command-line option STATIC=1. See "Command-Line Installation" for more information.
See "Java SE Runtime Environment Update Scenarios" for examples of how the installer performs.
