diff --git a/Library/Homebrew/extend/pathname.rb b/Library/Homebrew/extend/pathname.rb
index 01912337ad..91337f81d1 100644
--- a/Library/Homebrew/extend/pathname.rb
+++ b/Library/Homebrew/extend/pathname.rb
@@ -423,18 +423,15 @@ class Pathname
       script_name:  T.any(String, Pathname),
       java_opts:    String,
       java_version: T.nilable(String),
-      env:          T::Hash[Symbol, String],
     ).returns(Integer)
   }
-  def write_jar_script(target_jar, script_name, java_opts = "", java_version: nil, env: {})
-    env.merge!(Language::Java.overridable_java_home_env(java_version))
-    env_export = +""
-    env.each { |key, value| env_export << "#{key}=\"#{value}\" " }
+  def write_jar_script(target_jar, script_name, java_opts = "", java_version: nil)
     mkpath
-    (self/script_name).write <<~SH
+    (self/script_name).write <<~EOS
       #!/bin/bash
-      #{env_export}exec "${JAVA_HOME}/bin/java" #{java_opts} -jar "#{target_jar}" "$@"
-    SH
+      export JAVA_HOME="#{Language::Java.overridable_java_home_env(java_version)[:JAVA_HOME]}"
+      exec "${JAVA_HOME}/bin/java" #{java_opts} -jar "#{target_jar}" "$@"
+    EOS
   end
 
   def install_metafiles(from = Pathname.pwd)