#1888 use StringBuilderWriter instead of StringWriter in performance hotspot to reduce locking

jaxb-ri/runtime/impl/src/main/java/org/glassfish/jaxb/runtime/v2/runtime/output/StringBuilderWriter.java

@@ -0,0 +1,170 @@
+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one
+ *  or more contributor license agreements.  See the NOTICE file
+ *  distributed with this work for additional information
+ *  regarding copyright ownership.  The ASF licenses this file
+ *  to you 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.
+ */
+
+//@@3RD PARTY CODE@@
+
+package org.glassfish.jaxb.runtime.v2.runtime.output;
+
+import java.io.Serializable;
+import java.io.Writer;
+
+/**
+ * <p>
+ * Copied from
+ * <a href="https://github.com/apache/commons-io/blob/master/src/main/java/org/apache/commons/io/output/StringBuilderWriter.java">Apache commons-io</a>.
+ * <p>
+ * {@link Writer} implementation that outputs to a {@link StringBuilder}.
+ * <p>
+ * <strong>NOTE:</strong> This implementation, as an alternative to {@link java.io.StringWriter}, provides an
+ * <em>un-synchronized</em> implementation for better performance for use in a single thread. For safe usage with
+ * multiple {@link Thread}s, a {@link java.io.StringWriter} should be used.
+ */
+public class StringBuilderWriter extends Writer implements Serializable {
+
+    private static final long serialVersionUID = -146927496096066153L;
+
+    /** The append target. */
+    private final StringBuilder builder;
+
+    /**
+     * Constructs a new {@link StringBuilder} instance with default capacity.
+     */
+    public StringBuilderWriter() {
+        this.builder = new StringBuilder();
+    }
+
+    /**
+     * Constructs a new {@link StringBuilder} instance with the specified capacity.
+     *
+     * @param capacity The initial capacity of the underlying {@link StringBuilder}
+     */
+    public StringBuilderWriter(final int capacity) {
+        this.builder = new StringBuilder(capacity);
+    }
+
+    /**
+     * Constructs a new instance with the specified {@link StringBuilder}.
+     *
+     * <p>If {@code builder} is null a new instance with default capacity will be created.</p>
+     *
+     * @param builder The String builder. May be null.
+     */
+    public StringBuilderWriter(final StringBuilder builder) {
+        this.builder = builder != null ? builder : new StringBuilder();
+    }
+
+    /**
+     * Appends a single character to this Writer.
+     *
+     * @param value The character to append
+     * @return This writer instance
+     */
+    @Override
+    public Writer append(final char value) {
+        builder.append(value);
+        return this;
+    }
+
+    /**
+     * Appends a character sequence to this Writer.
+     *
+     * @param value The character to append
+     * @return This writer instance
+     */
+    @Override
+    public Writer append(final CharSequence value) {
+        builder.append(value);
+        return this;
+    }
+
+    /**
+     * Appends a portion of a character sequence to the {@link StringBuilder}.
+     *
+     * @param value The character to append
+     * @param start The index of the first character
+     * @param end The index of the last character + 1
+     * @return This writer instance
+     */
+    @Override
+    public Writer append(final CharSequence value, final int start, final int end) {
+        builder.append(value, start, end);
+        return this;
+    }
+
+    /**
+     * Closing this writer has no effect.
+     */
+    @Override
+    public void close() {
+        // no-op
+    }
+
+    /**
+     * Flushing this writer has no effect.
+     */
+    @Override
+    public void flush() {
+        // no-op
+    }
+
+    /**
+     * Gets the underlying builder.
+     *
+     * @return The underlying builder
+     */
+    public StringBuilder getBuilder() {
+        return builder;
+    }
+
+    /**
+     * Returns {@link StringBuilder#toString()}.
+     *
+     * @return The contents of the String builder.
+     */
+    @Override
+    public String toString() {
+        return builder.toString();
+    }
+
+    /**
+     * Writes a portion of a character array to the {@link StringBuilder}.
+     *
+     * @param value The value to write
+     * @param offset The index of the first character
+     * @param length The number of characters to write
+     */
+    @Override
+    public void write(final char[] value, final int offset, final int length) {
+        if (value != null) {
+            builder.append(value, offset, length);
+        }
+    }
+
+    /**
+     * Writes a String to the {@link StringBuilder}.
+     *
+     * @param value The value to write
+     */
+    @Override
+    public void write(final String value) {
+        if (value != null) {
+            builder.append(value);
+        }
+    }
+}

jaxb-ri/runtime/impl/src/main/java/org/glassfish/jaxb/runtime/v2/runtime/output/UTF8XmlOutput.java

@@ -20,7 +20,6 @@
 import javax.xml.stream.XMLStreamException;
 import java.io.IOException;
 import java.io.OutputStream;
-import java.io.StringWriter;
 
 /**
  * {@link XmlOutput} implementation specialized for UTF-8.
@@ -160,7 +159,7 @@ private int pushNsDecls() {
 
             Encoded e = prefixes[i];
 
-            if(p.length()==0) {
+            if(p.isEmpty()) {
                 e.buf = EMPTY_BYTE_ARRAY;
                 e.len = 0;
             } else {
@@ -186,9 +185,8 @@ protected void writeNsDecls(int base) throws IOException {
     protected final void writeNsDecl(int prefixIndex) throws IOException {
         String p = nsContext.getPrefix(prefixIndex);
 
-        if(p.length()==0) {
-            if(nsContext.getCurrent().isRootElement()
-            && nsContext.getNamespaceURI(prefixIndex).length()==0)
+        if(p.isEmpty()) {
+            if(nsContext.getCurrent().isRootElement() && nsContext.getNamespaceURI(prefixIndex).isEmpty())
                 return;     // no point in declaring xmlns="" on the root element
             write(XMLNS_EQUALS);
         } else {
@@ -288,7 +286,7 @@ public void text(Pcdata value, boolean needSP) throws IOException {
 
     private void doText(String value,boolean isAttribute) throws IOException {
         if (escapeHandler != null) {
-            StringWriter sw = new StringWriter();
+            StringBuilderWriter sw = new StringBuilderWriter();
             escapeHandler.escape(value.toCharArray(), 0, value.length(), isAttribute, sw);
             textBuffer.set(sw.toString());
         } else {

jaxb-ri/tools/config/copyright-exclude

@@ -39,6 +39,7 @@ jing-copying.html
 /rngom/src/test/java/Main.java
 
 /runtime/impl/src/main/java/com/sun/xml/bind/marshaller/XMLWriter.java
+/runtime/impl/src/main/java/org/glassfish/jaxb/runtime/v2/runtime/output/StringBuilderWriter.java
 
 /tools/pretty-printer/src/com/sun/tools/xmlpp/DataWriter.java
 /tools/pretty-printer/src/com/sun/tools/xmlpp/XMLWriter.java