Introduced SpringProperties class and optional "spring.properties" file

This in particular allows for specifying "spring.getenv.ignore" and "spring.beaninfo.ignore" in a local way within the application, in case that JVM-level system properties are locked.

Issue: SPR-9014
Issue: SPR-11297
(cherry picked from commit 8543b91)

spring-beans/src/main/java/org/springframework/beans/CachedIntrospectionResults.java

@@ -33,6 +33,7 @@ import java.util.WeakHashMap;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import org.springframework.core.SpringProperties;
 import org.springframework.core.io.support.SpringFactoriesLoader;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.StringUtils;
@@ -114,17 +115,7 @@ public class CachedIntrospectionResults {
 
 
 	static {
-		boolean ignoreValue;
-		try {
-			ignoreValue = "true".equalsIgnoreCase(System.getProperty(IGNORE_BEANINFO_PROPERTY_NAME));
-		}
-		catch (Throwable ex) {
-			if (logger.isDebugEnabled()) {
-				logger.debug("Could not obtain system property '" + IGNORE_BEANINFO_PROPERTY_NAME + "': " + ex);
-			}
-			ignoreValue = false;
-		}
-		shouldIntrospectorIgnoreBeaninfoClasses = ignoreValue;
+		shouldIntrospectorIgnoreBeaninfoClasses = SpringProperties.getFlag(IGNORE_BEANINFO_PROPERTY_NAME);
 	}
 
 
@@ -293,16 +284,19 @@ public class CachedIntrospectionResults {
 			}
 			this.beanInfo = beanInfo;
 
-			// Immediately remove class from Introspector cache, to allow for proper
-			// garbage collection on class loader shutdown - we cache it here anyway,
-			// in a GC-friendly manner. In contrast to CachedIntrospectionResults,
-			// Introspector does not use WeakReferences as values of its WeakHashMap!
-			Class<?> classToFlush = beanClass;
-			do {
-				Introspector.flushFromCaches(classToFlush);
-				classToFlush = classToFlush.getSuperclass();
+			// Only bother with flushFromCaches if the Introspector actually cached...
+			if (!shouldIntrospectorIgnoreBeaninfoClasses) {
+				// Immediately remove class from Introspector cache, to allow for proper
+				// garbage collection on class loader shutdown - we cache it here anyway,
+				// in a GC-friendly manner. In contrast to CachedIntrospectionResults,
+				// Introspector does not use WeakReferences as values of its WeakHashMap!
+				Class<?> classToFlush = beanClass;
+				do {
+					Introspector.flushFromCaches(classToFlush);
+					classToFlush = classToFlush.getSuperclass();
+				}
+				while (classToFlush != null);
 			}
-			while (classToFlush != null);
 
 			if (logger.isTraceEnabled()) {
 				logger.trace("Caching PropertyDescriptors for class [" + beanClass.getName() + "]");

spring-beans/src/main/java/org/springframework/beans/factory/config/PropertyPlaceholderConfigurer.java

@@ -21,6 +21,7 @@ import java.util.Set;
 
 import org.springframework.beans.BeansException;
 import org.springframework.core.Constants;
+import org.springframework.core.SpringProperties;
 import org.springframework.core.env.AbstractEnvironment;
 import org.springframework.util.PropertyPlaceholderHelper;
 import org.springframework.util.PropertyPlaceholderHelper.PlaceholderResolver;
@@ -84,7 +85,7 @@ public class PropertyPlaceholderConfigurer extends PlaceholderConfigurerSupport
 	private int systemPropertiesMode = SYSTEM_PROPERTIES_MODE_FALLBACK;
 
 	private boolean searchSystemEnvironment =
-			!"true".equalsIgnoreCase(System.getProperty(AbstractEnvironment.IGNORE_GETENV_PROPERTY_NAME));
+			!SpringProperties.getFlag(AbstractEnvironment.IGNORE_GETENV_PROPERTY_NAME);
 
 
 	/**

spring-core/src/main/java/org/springframework/core/SpringProperties.java

@@ -0,0 +1,130 @@
+/*
+ * Copyright 2002-2013 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.core;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.util.Properties;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+/**
+ * Static holder for local Spring properties, i.e. defined at the Spring library level.
+ *
+ * <p>Reads a {@code spring.properties} file from the root of the Spring library classpath,
+ * and also allows for programmatically setting properties through {@link #setProperty}.
+ * When checking a property, local entries are being checked first, then falling back
+ * to JVM-level system properties through a {@link System#getProperty} check.
+ *
+ * <p>This is an alternative way to set Spring-related system properties such as
+ * "spring.getenv.ignore" and "spring.beaninfo.ignore", in particular for scenarios
+ * where JVM system properties are locked on the target platform (e.g. WebSphere).
+ * See {@link #setFlag} for a convenient way to locally set such flags to "true".
+ *
+ * @author Juergen Hoeller
+ * @since 3.2.7
+ * @see org.springframework.core.env.AbstractEnvironment#IGNORE_GETENV_PROPERTY_NAME
+ * @see org.springframework.beans.CachedIntrospectionResults#IGNORE_BEANINFO_PROPERTY_NAME
+ */
+public abstract class SpringProperties {
+
+	private static final Log logger = LogFactory.getLog(SpringProperties.class);
+
+	private static final Properties localProperties = new Properties();
+
+
+	static {
+		try {
+			ClassLoader cl = SpringProperties.class.getClassLoader();
+			URL url = cl.getResource("spring.properties");
+			if (url != null) {
+				logger.info("Found 'spring.properties' file in local classpath");
+				InputStream is = url.openStream();
+				try {
+					localProperties.load(is);
+				}
+				finally {
+					is.close();
+				}
+			}
+		}
+		catch (IOException ex) {
+			if (logger.isInfoEnabled()) {
+				logger.info("Could not load 'spring.properties' file from local classpath: " + ex);
+			}
+		}
+	}
+
+
+	/**
+	 * Programmatically set a local property, overriding an entry in the
+	 * {@code spring.properties} file (if any).
+	 * @param key the property key
+	 * @param value the associated property value, or {@code null} to reset it
+	 */
+	public static void setProperty(String key, String value) {
+		if (value != null) {
+			localProperties.setProperty(key, value);
+		}
+		else {
+			localProperties.remove(key);
+		}
+	}
+
+	/**
+	 * Retrieve the property value for the given key, checking local Spring
+	 * properties first and falling back to JVM-level system properties.
+	 * @param key the property key
+	 * @return the associated property value, or {@code null} if none found
+	 */
+	public static String getProperty(String key) {
+		String value = localProperties.getProperty(key);
+		if (value == null) {
+			try {
+				value = System.getProperty(key);
+			}
+			catch (Throwable ex) {
+				if (logger.isDebugEnabled()) {
+					logger.debug("Could not retrieve system property '" + key + "': " + ex);
+				}
+			}
+		}
+		return value;
+	}
+
+	/**
+	 * Programmatically set a local flag to "true", overriding an
+	 * entry in the {@code spring.properties} file (if any).
+	 * @param key the property key
+	 */
+	public static void setFlag(String key) {
+		localProperties.put(key, Boolean.TRUE.toString());
+	}
+
+	/**
+	 * Retrieve the flag for the given property key.
+	 * @param key the property key
+	 * @return {@code true} if the property is set to "true",
+	 * {@code} false otherwise
+	 */
+	public static boolean getFlag(String key) {
+		return Boolean.parseBoolean(getProperty(key));
+	}
+
+}

spring-core/src/main/java/org/springframework/core/env/AbstractEnvironment.java

@@ -25,6 +25,7 @@ import java.util.Set;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import org.springframework.core.SpringProperties;
 import org.springframework.core.convert.support.ConfigurableConversionService;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
@@ -369,15 +370,15 @@ public abstract class AbstractEnvironment implements ConfigurableEnvironment {
 		catch (AccessControlException ex) {
 			return (Map) new ReadOnlySystemAttributesMap() {
 				@Override
-				protected String getSystemAttribute(String variableName) {
+				protected String getSystemAttribute(String attributeName) {
 					try {
-						return System.getenv(variableName);
+						return System.getenv(attributeName);
 					}
 					catch (AccessControlException ex) {
 						if (logger.isInfoEnabled()) {
 							logger.info(format("Caught AccessControlException when accessing system " +
 									"environment variable [%s]; its value will be returned [null]. Reason: %s",
-									variableName, ex.getMessage()));
+									attributeName, ex.getMessage()));
 						}
 						return null;
 					}
@@ -396,15 +397,7 @@ public abstract class AbstractEnvironment implements ConfigurableEnvironment {
 	 * returning {@code true} if its value equals "true" in any case.
 	 */
 	protected boolean suppressGetenvAccess() {
-		try {
-			return "true".equalsIgnoreCase(System.getProperty(IGNORE_GETENV_PROPERTY_NAME));
-		}
-		catch (Throwable ex) {
-			if (logger.isDebugEnabled()) {
-				logger.debug("Could not obtain system property '" + IGNORE_GETENV_PROPERTY_NAME + "': " + ex);
-			}
-			return false;
-		}
+		return SpringProperties.getFlag(IGNORE_GETENV_PROPERTY_NAME);
 	}
 
 	@SuppressWarnings("unchecked")
@@ -415,15 +408,15 @@ public abstract class AbstractEnvironment implements ConfigurableEnvironment {
 		catch (AccessControlException ex) {
 			return (Map) new ReadOnlySystemAttributesMap() {
 				@Override
-				protected String getSystemAttribute(String propertyName) {
+				protected String getSystemAttribute(String attributeName) {
 					try {
-						return System.getProperty(propertyName);
+						return System.getProperty(attributeName);
 					}
 					catch (AccessControlException ex) {
 						if (logger.isInfoEnabled()) {
 							logger.info(format("Caught AccessControlException when accessing system " +
 									"property [%s]; its value will be returned [null]. Reason: %s",
-									propertyName, ex.getMessage()));
+									attributeName, ex.getMessage()));
 						}
 						return null;
 					}

spring-core/src/test/java/org/springframework/core/env/StandardEnvironmentTests.java

@@ -17,19 +17,17 @@
 package org.springframework.core.env;
 
 import java.lang.reflect.Field;
-
 import java.security.AccessControlException;
 import java.security.Permission;
-
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.Map;
 
 import org.junit.Test;
+
+import org.springframework.core.SpringProperties;
 import org.springframework.mock.env.MockPropertySource;
 
-
-import static java.lang.String.*;
 import static org.hamcrest.Matchers.*;
 import static org.junit.Assert.*;
 import static org.springframework.core.env.AbstractEnvironment.*;
@@ -38,6 +36,7 @@ import static org.springframework.core.env.AbstractEnvironment.*;
  * Unit tests for {@link StandardEnvironment}.
  *
  * @author Chris Beams
+ * @author Juergen Hoeller
  */
 public class StandardEnvironmentTests {
 
@@ -60,15 +59,15 @@ public class StandardEnvironmentTests {
 		child.setActiveProfiles("c1", "c2");
 		child.getPropertySources().addLast(
 				new MockPropertySource("childMock")
-					.withProperty("childKey", "childVal")
-					.withProperty("bothKey", "childBothVal"));
+						.withProperty("childKey", "childVal")
+						.withProperty("bothKey", "childBothVal"));
 
 		ConfigurableEnvironment parent = new StandardEnvironment();
 		parent.setActiveProfiles("p1", "p2");
 		parent.getPropertySources().addLast(
 				new MockPropertySource("parentMock")
-					.withProperty("parentKey", "parentVal")
-					.withProperty("bothKey", "parentBothVal"));
+						.withProperty("parentKey", "parentVal")
+						.withProperty("bothKey", "parentBothVal"));
 
 		assertThat(child.getProperty("childKey"), is("childVal"));
 		assertThat(child.getProperty("parentKey"), nullValue());
@@ -334,12 +333,27 @@ public class StandardEnvironmentTests {
 		try {
 			env.addActiveProfile("invalid-profile");
 			fail("expected validation exception");
-		} catch (IllegalArgumentException ex) {
+		}
+		catch (IllegalArgumentException ex) {
 			assertThat(ex.getMessage(),
 					equalTo("Invalid profile [invalid-profile]: must not contain dash character"));
 		}
 	}
 
+	@Test
+	public void suppressGetenvAccessThroughSystemProperty() {
+		System.setProperty("spring.getenv.ignore", "true");
+		assertTrue(environment.getSystemEnvironment().isEmpty());
+		System.clearProperty("spring.getenv.ignore");
+	}
+
+	@Test
+	public void suppressGetenvAccessThroughSpringProperty() {
+		SpringProperties.setProperty("spring.getenv.ignore", "true");
+		assertTrue(environment.getSystemEnvironment().isEmpty());
+		SpringProperties.setProperty("spring.getenv.ignore", null);
+	}
+
 	@Test
 	public void getSystemProperties_withAndWithoutSecurityManager() {
 		System.setProperty(ALLOWED_PROPERTY_NAME, ALLOWED_PROPERTY_VALUE);
@@ -371,7 +385,7 @@ public class StandardEnvironmentTests {
 				// see http://download.oracle.com/javase/1.5.0/docs/api/java/lang/System.html#getProperty(java.lang.String)
 				if (DISALLOWED_PROPERTY_NAME.equals(key)) {
 					throw new AccessControlException(
-							format("Accessing the system property [%s] is disallowed", DISALLOWED_PROPERTY_NAME));
+							String.format("Accessing the system property [%s] is disallowed", DISALLOWED_PROPERTY_NAME));
 				}
 			}
 			@Override
@@ -402,7 +416,8 @@ public class StandardEnvironmentTests {
 			try {
 				systemProperties.get(NON_STRING_PROPERTY_NAME);
 				fail("Expected IllegalArgumentException when searching with non-string key against ReadOnlySystemAttributesMap");
-			} catch (IllegalArgumentException ex) {
+			}
+			catch (IllegalArgumentException ex) {
 				// expected
 			}
 		}
@@ -436,7 +451,7 @@ public class StandardEnvironmentTests {
 				//see http://download.oracle.com/javase/1.5.0/docs/api/java/lang/System.html#getenv(java.lang.String)
 				if (("getenv."+DISALLOWED_PROPERTY_NAME).equals(perm.getName())) {
 					throw new AccessControlException(
-							format("Accessing the system environment variable [%s] is disallowed", DISALLOWED_PROPERTY_NAME));
+							String.format("Accessing the system environment variable [%s] is disallowed", DISALLOWED_PROPERTY_NAME));
 				}
 			}
 		};
@@ -469,7 +484,8 @@ public class StandardEnvironmentTests {
 					if (obj != null && obj.getClass().getName().equals("java.lang.ProcessEnvironment$StringEnvironment")) {
 						return (Map<String, String>) obj;
 					}
-				} catch (Exception ex) {
+				}
+				catch (Exception ex) {
 					throw new RuntimeException(ex);
 				}
 			}
@@ -479,8 +495,9 @@ public class StandardEnvironmentTests {
 		Class<?> processEnvironmentClass;
 		try {
 			processEnvironmentClass = Class.forName("java.lang.ProcessEnvironment");
-		} catch (Exception e) {
-			throw new RuntimeException(e);
+		}
+		catch (Exception ex) {
+			throw new IllegalStateException(ex);
 		}
 
 		try {
@@ -488,10 +505,12 @@ public class StandardEnvironmentTests {
 			theCaseInsensitiveEnvironmentField.setAccessible(true);
 			Object obj = theCaseInsensitiveEnvironmentField.get(null);
 			return (Map<String, String>) obj;
-		} catch (NoSuchFieldException e) {
+		}
+		catch (NoSuchFieldException ex) {
 			// do nothing
-		} catch (Exception e) {
-			throw new RuntimeException(e);
+		}
+		catch (Exception ex) {
+			throw new IllegalStateException(ex);
 		}
 
 		try {
@@ -499,12 +518,15 @@ public class StandardEnvironmentTests {
 			theEnvironmentField.setAccessible(true);
 			Object obj = theEnvironmentField.get(null);
 			return (Map<String, String>) obj;
-		} catch (NoSuchFieldException e) {
+		}
+		catch (NoSuchFieldException ex) {
 			// do nothing
-		} catch (Exception e) {
-			throw new RuntimeException(e);
+		}
+		catch (Exception ex) {
+			throw new IllegalStateException(ex);
 		}
 
 		throw new IllegalStateException();
 	}
+
 }