1 files changed, 136 insertions, 0 deletions
diff --git a/tools/tools-common/src/main/java/org/onap/policy/apex/tools/common/OutputFile.java b/tools/tools-common/src/main/java/org/onap/policy/apex/tools/common/OutputFile.java
new file mode 100644
index 000000000..b529a7e08
--- /dev/null
+++ b/tools/tools-common/src/main/java/org/onap/policy/apex/tools/common/OutputFile.java
@@ -0,0 +1,136 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.tools.common;
+
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.Writer;
+import java.nio.file.FileSystems;
+import java.nio.file.Path;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.Validate;
+
+/**
+ * Standard output file handling and tests.
+ *
+ * @author Sven van der Meer (sven.van.der.meer@ericsson.com)
+ */
+public class OutputFile {
+
+    /** The output file name. */
+    private final String fileName;
+
+    /** The output file name. */
+    private final boolean overwrite;
+
+    /**
+     * Creates a new object for a given file name.
+     *
+     * @param fileName the file name
+     */
+    public OutputFile(final String fileName) {
+        this(fileName, false);
+    }
+
+    /**
+     * Creates a new object for a given file name.
+     *
+     * @param fileName the file name
+     * @param overwrite if the file already exists, can it be overwritten, or should an error be raised
+     */
+    public OutputFile(final String fileName, final boolean overwrite) {
+        Validate.notBlank(fileName);
+        this.fileName = fileName;
+        this.overwrite = overwrite;
+    }
+
+    /**
+     * Get a File object for this output file.
+     *
+     * @return a File object for this output file
+     */
+    public File toFile() {
+        final Path fp = FileSystems.getDefault().getPath(fileName);
+        return fp.toFile();
+    }
+
+    /**
+     * Get a Writer object for this output file.
+     *
+     * @return a Writer object for this output file
+     */
+    public Writer toWriter() {
+        try {
+            return new BufferedWriter(new FileWriter(toFile()));
+        } catch (final IOException e) {
+            return null;
+        }
+    }
+
+    /**
+     * Get a OutputStream object for this output file.
+     *
+     * @return an OutputStream object for this output file
+     */
+    public OutputStream toOutputStream() {
+        try {
+            return new FileOutputStream(toFile());
+        } catch (final IOException e) {
+            return null;
+        }
+    }
+
+    /**
+     * Validates the output file. Validation tests for file name being blank, file existing, creation, and finally
+     * can-write.
+     *
+     * @return null on success, an error message on error
+     */
+    public String validate() {
+        if (StringUtils.isBlank(fileName)) {
+            return "file name was blank";
+        }
+
+        final File file = toFile();
+        if (file.exists()) {
+            if (!overwrite) {
+                return "file already exists";
+            }
+        } else {
+            try {
+                file.createNewFile();
+            } catch (final IOException e) {
+                return "could not create output file: " + e.getMessage();
+            }
+        }
+
+        if (!file.canWrite()) {
+            return "cannot write to file";
+        }
+
+        return null;
+    }
+}