1 files changed, 162 insertions, 0 deletions
diff --git a/src/main/java/com/amazon/carbonado/lob/AbstractClob.java b/src/main/java/com/amazon/carbonado/lob/AbstractClob.java
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+++ b/src/main/java/com/amazon/carbonado/lob/AbstractClob.java
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+/*
+ * Copyright 2006 Amazon Technologies, Inc. or its affiliates.
+ * Amazon, Amazon.com and Carbonado are trademarks or registered trademarks
+ * of Amazon Technologies, Inc. or its affiliates.  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.
+ */
+
+package com.amazon.carbonado.lob;
+
+import java.io.IOException;
+import java.io.Reader;
+import java.io.Writer;
+
+import com.amazon.carbonado.FetchException;
+import com.amazon.carbonado.PersistException;
+import com.amazon.carbonado.Repository;
+import com.amazon.carbonado.Transaction;
+
+/**
+ * AbstractClob implements a small set of common Clob methods.
+ *
+ * @author Brian S O'Neill
+ */
+public abstract class AbstractClob implements Clob {
+    static FetchException toFetchException(IOException e) {
+        Throwable cause = e.getCause();
+        if (cause instanceof FetchException) {
+            return (FetchException) cause;
+        }
+        if (cause == null) {
+            cause = e;
+        }
+        return new FetchException(cause);
+    }
+
+    static PersistException toPersistException(IOException e) {
+        Throwable cause = e.getCause();
+        if (cause instanceof PersistException) {
+            return (PersistException) cause;
+        }
+        if (cause == null) {
+            cause = e;
+        }
+        return new PersistException(cause);
+    }
+
+    private final Repository mRepo;
+
+    protected AbstractClob() {
+        mRepo = null;
+    }
+
+    /**
+     * Use of this constructor indicates that setValue should operate within a
+     * transaction. A Repository is passed in for entering the transaction.
+     *
+     * @param repo optional repository to use for performing string conversion
+     * within transactions
+     */
+    protected AbstractClob(Repository repo) {
+        mRepo = repo;
+    }
+
+    public String asString() throws FetchException {
+        Transaction txn = mRepo == null ? null : mRepo.enterTransaction();
+        try {
+            long length = getLength();
+
+            if (length > Integer.MAX_VALUE) {
+                throw new IllegalArgumentException
+                    ("Clob is too long to fit in a String: " + length);
+            }
+
+            int iLen = (int) length;
+
+            if (iLen <= 0) {
+                return "";
+            }
+
+            try {
+                Reader r = openReader();
+
+                char[] buf = new char[iLen];
+                int offset = 0;
+                int amt;
+                while ((amt = r.read(buf, offset, iLen - offset)) > 0) {
+                    offset += amt;
+                }
+                r.close();
+
+                if (offset <= 0) {
+                    return "";
+                }
+
+                return new String(buf, 0, offset);
+            } catch (IOException e) {
+                throw toFetchException(e);
+            }
+        } finally {
+            if (txn != null) {
+                try {
+                    txn.exit();
+                } catch (PersistException e) {
+                    // Don't care.
+                }
+            }
+        }
+    }
+
+    public void setValue(String value) throws PersistException {
+        if (value == null) {
+            throw new IllegalArgumentException("Clob value cannot be null");
+        }
+
+        if (mRepo == null) {
+            setLength(0);
+            try {
+                Writer w = openWriter();
+                w.write(value);
+                w.close();
+            } catch (IOException e) {
+                throw toPersistException(e);
+            }
+        } else {
+            Transaction txn = mRepo.enterTransaction();
+
+            try {
+                long originalLength = getLength();
+
+                try {
+                    Writer w = openWriter();
+                    w.write(value);
+                    w.close();
+                } catch (IOException e) {
+                    throw toPersistException(e);
+                }
+
+                if (value.length() < originalLength) {
+                    // Truncate.
+                    setLength(value.length());
+                }
+
+                txn.commit();
+            } catch (FetchException e) {
+                throw e.toPersistException();
+            } finally {
+                txn.exit();
+            }
+        }
+    }
+}