Initial Contribution

tools/androidprefs/src/com/android/prefs/AndroidLocation.java

@@ -0,0 +1,153 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * 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 com.android.prefs;
+
+import java.io.File;
+
+/**
+ * Manages the location of the android files (including emulator files, ddms config, debug keystore)
+ */
+public final class AndroidLocation {
+    
+    /**
+     * Used to know where to store the user data image.
+     * <p/>
+     * This <em>must</em> match the constant ANDROID_SDK_VERSION used by the emulator
+     * to find its own emulator images. It is defined in tools/qemu/android.h
+     */
+    private static final String ANDROID_SDK_VERSION = "SDK-1.0";
+
+    /**
+     * Throw when the location of the android folder couldn't be found.
+     */
+    public static final class AndroidLocationException extends Exception {
+        private static final long serialVersionUID = 1L;
+
+        public AndroidLocationException(String string) {
+            super(string);
+        }
+    }
+    
+    private static String sPrefsLocation = null;
+    
+    /**
+     * Returns the folder used to store android related files.
+     * @return an OS specific path, terminated by a separator.
+     * @throws AndroidLocationException 
+     */
+    public final static String getFolder() throws AndroidLocationException {
+        if (sPrefsLocation == null) {
+            String osName = System.getProperty("os.name");
+
+            // First we check for unknown or non windows OS.
+            if (osName == null || osName.startsWith("Windows") == false) {
+                String home = findValidPath("user.home", "HOME");
+
+                if (home != null) {
+                    sPrefsLocation = home + File.separator + ".android" + File.separator;
+                }
+            } else {
+                String localAppData = findValidPath("LOCALAPPDATA");
+                if (localAppData == null) {
+                    localAppData = findValidPath("USERPROFILE");
+                    if (localAppData != null) {
+                        localAppData = localAppData + "\\Local Settings\\Application Data";
+                        
+                        // check that this directory exists.
+                        File f = new File(localAppData);
+                        if (f.isDirectory() == false) {
+                            localAppData = null;
+                        }
+                    }
+
+                    // ok if nothing worked, revert to HOME
+                    if (localAppData == null) {
+                        localAppData = findValidPath("HOME", "user.home");
+                    }
+                }
+                
+                if (localAppData != null) {
+                    sPrefsLocation = localAppData + "\\Android\\";
+                }
+            }
+            
+            // if all the above failed, try to create a temporary file to get its parent and
+            // use that as the folder
+            if (sPrefsLocation == null) {
+                // no home dir?
+                throw new AndroidLocationException(
+                        "Unable to get the home directory. Make sure the user.home property is set up");
+            } else {
+                // make sure the folder exists!
+                File f = new File(sPrefsLocation);
+                if (f.exists() == false) {
+                    f.mkdir();
+                } else if (f.isFile()) {
+                    throw new AndroidLocationException(sPrefsLocation +
+                            " is not a directory! This is required to run Android tools.");
+                }
+            }
+        }
+        
+        return sPrefsLocation;
+    }
+
+    /**
+     * Returns the folder where the emulator is going to find its android related files.
+     * @return an OS specific path, terminated by a separator.
+     * @throws AndroidLocationException 
+     */
+    public final static String getEmulatorFolder() throws AndroidLocationException {
+        String path = getFolder() + ANDROID_SDK_VERSION + File.separator;
+        
+        File f = new File(path);
+        if (f.exists() == false) {
+            f.mkdir();
+        } else if (f.isFile()) {
+            throw new AndroidLocationException(path +
+                    " is not a directory! This is required to run Android tools.");
+        }
+
+        return path;
+    }
+
+    /**
+     * Checks a list of system properties and/or system environment variables for validity, and
+     * existing director, and returns the first one.
+     * @param names
+     * @return the content of the first property/variable.
+     */
+    private static String findValidPath(String... names) {
+        for (String name : names) {
+            String path;
+            if (name.indexOf('.') != -1) {
+                path = System.getProperty(name);
+            } else {
+                path = System.getenv(name);
+            }
+
+            if (path != null) {
+                File f = new File(path);
+                if (f.isDirectory()) {
+                    return path;
+                }
+            }
+        }
+        
+        return null;
+    }
+}