[LANG-1393] Add API SystemUtils.String getEnvironmentVariable(final

String name, final String defaultValue).

1 files changed, 27 insertions, 0 deletions

diff --git a/src/main/java/org/apache/commons/lang3/SystemUtils.java b/src/main/java/org/apache/commons/lang3/SystemUtils.java
index f91628a4b..2289d5d2d 100644
--- a/src/main/java/org/apache/commons/lang3/SystemUtils.java
+++ b/src/main/java/org/apache/commons/lang3/SystemUtils.java
@@ -1607,6 +1607,33 @@ public class SystemUtils {
 
     /**
      * <p>
+     * Gets an environment variable, defaulting to {@code defaultValue} if the variable cannot be read.
+     * </p>
+     * <p>
+     * If a {@code SecurityException} is caught, the return value is {@code defaultValue} and a message is written to
+     * {@code System.err}.
+     * </p>
+     *
+     * @param name
+     *            the environment variable name
+     * @param defaultValue
+     *            the default value
+     * @return the environment variable value or {@code defaultValue} if a security problem occurs
+     * @since 3.7
+     */
+    public static String getEnvironmentVariable(final String name, final String defaultValue) {
+        try {
+            final String value = System.getenv(name);
+            return value == null ? defaultValue : value;
+        } catch (final SecurityException ex) {
+            // we are not allowed to look at this property
+            System.err.println("Caught a SecurityException reading the environment variable '" + name + "'.");
+            return defaultValue;
+        }
+    }
+
+    /**
+     * <p>
      * Gets the user directory as a {@code File}.
      * </p>
      *