First Step in optimizing GSP Performance on Grails 7. Safe small optimizations to start

grails-gsp/core/src/main/groovy/org/grails/gsp/GroovyPage.java

@@ -23,7 +23,6 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -84,6 +83,7 @@ public abstract class GroovyPage extends Script {
     public static final String LINK_NAMESPACE = "link";
     public static final String TEMPLATE_NAMESPACE = "tmpl";
     public static final String PAGE_SCOPE = "pageScope";
+    private OutputEncodingStackAttributes.Builder attributesBuilder;
 
     public static final Collection<String> RESERVED_NAMES = CollectionUtils.newSet(
             OUT,
@@ -130,23 +130,30 @@ public void setOut(Writer newWriter) {
         throw new IllegalStateException("Setting out in page isn't allowed.");
     }
 
-    public void initRun(Writer target, OutputContext outputContext, GroovyPageMetaInfo metaInfo) {
-        OutputEncodingStackAttributes.Builder attributesBuilder = new OutputEncodingStackAttributes.Builder();
+    public void initCommonRun(GroovyPageMetaInfo metaInfo) {
+        attributesBuilder = new OutputEncodingStackAttributes.Builder();
         if (metaInfo != null) {
-            setJspTags(metaInfo.getJspTags());
-            setJspTagLibraryResolver(metaInfo.getJspTagLibraryResolver());
-            setGspTagLibraryLookup(metaInfo.getTagLibraryLookup());
-            setHtmlParts(metaInfo.getHtmlParts());
-            setPluginContextPath(metaInfo.getPluginPath());
             attributesBuilder.outEncoder(metaInfo.getOutEncoder());
             attributesBuilder.staticEncoder(metaInfo.getStaticEncoder());
             attributesBuilder.expressionEncoder(metaInfo.getExpressionEncoder());
             attributesBuilder.defaultTaglibEncoder(metaInfo.getTaglibEncoder());
+            setHtmlParts(metaInfo.getHtmlParts());
+            setHtmlPartsSet(metaInfo.getHtmlPartsSet());
+            setJspTags(metaInfo.getJspTags());
+            setJspTagLibraryResolver(metaInfo.getJspTagLibraryResolver());
+            setGspTagLibraryLookup(metaInfo.getTagLibraryLookup());
+            setPluginContextPath(metaInfo.getPluginPath());
+        }
+        attributesBuilder.allowCreate(true).autoSync(false).pushTop(true);
+        attributesBuilder.inheritPreviousEncoders(false);
+    }
+
+    public void initRun(Writer target, OutputContext outputContext, GroovyPageMetaInfo metaInfo) {
+        if (metaInfo != null) {
             applyModelFieldsFromBinding(metaInfo.getModelFields());
         }
-        attributesBuilder.allowCreate(true).topWriter(target).autoSync(false).pushTop(true);
         attributesBuilder.outputContext(outputContext);
-        attributesBuilder.inheritPreviousEncoders(false);
+        attributesBuilder.topWriter(target);
         outputStack = OutputEncodingStack.currentStack(attributesBuilder.build());
 
         out = outputStack.getOutWriter();
@@ -507,6 +514,14 @@ public final void printHtmlPart(final int partNumber) {
         staticOut.write(htmlParts[partNumber]);
     }
 
+    /**
+     * Shorthand for printHtmlPart to reduce class size
+     * @param partNumber
+     */
+    public final void h(final int partNumber) {
+        staticOut.write(htmlParts[partNumber]);
+    }
+
     /**
      * Sets the JSP tags used by this GroovyPage instance
      *
@@ -527,14 +542,10 @@ protected boolean isHtmlPart(String htmlPart) {
 
     public void setHtmlParts(String[] htmlParts) {
         this.htmlParts = htmlParts;
-        this.htmlPartsSet = new HashSet<>();
-        if (htmlParts != null) {
-            for (String htmlPart : htmlParts) {
-                if (htmlPart != null) {
-                    htmlPartsSet.add(System.identityHashCode(htmlPart));
-                }
-            }
-        }
+    }
+
+    public void setHtmlPartsSet(Set<Integer> htmlPartsSet) {
+        this.htmlPartsSet = htmlPartsSet;
     }
 
     public final OutputEncodingStack getOutputStack() {

grails-gsp/core/src/main/groovy/org/grails/gsp/GroovyPageMetaInfo.java

@@ -22,7 +22,10 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.Writer;
+import java.lang.ref.SoftReference;
+import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Modifier;
 import java.net.URL;
 import java.net.URLConnection;
@@ -67,14 +70,17 @@ public class GroovyPageMetaInfo implements GrailsApplicationAware {
     private static final Log LOG = LogFactory.getLog(GroovyPageMetaInfo.class);
     private TagLibraryLookup tagLibraryLookup;
     private TagLibraryResolver jspTagLibraryResolver;
+    private ThreadLocal<SoftReference<GroovyPage>> pageInstance = new ThreadLocal<>();
 
     private boolean precompiledMode = false;
     private Class<?> pageClass;
+    private Constructor<?> pageClassConstructor;
     private long lastModified;
     private InputStream groovySource;
     private String contentType;
     private int[] lineNumbers;
     private String[] htmlParts;
+    private Set<Integer> htmlPartsSet;
     @SuppressWarnings("rawtypes")
     private Map jspTags = Collections.emptyMap();
     private GroovyPagesException compilationException;
@@ -115,6 +121,11 @@ public GroovyPageMetaInfo(Class<?> pageClass) {
         this();
         precompiledMode = true;
         this.pageClass = pageClass;
+        try {
+            this.pageClassConstructor = pageClass.getConstructor();
+        } catch (NoSuchMethodException e) {
+            throw new RuntimeException(e);
+        }
         contentType = (String) ReflectionUtils.getField(ReflectionUtils.findField(pageClass, GroovyPageParser.CONSTANT_NAME_CONTENT_TYPE), null);
         jspTags = (Map) ReflectionUtils.getField(ReflectionUtils.findField(pageClass, GroovyPageParser.CONSTANT_NAME_JSP_TAGS), null);
         lastModified = (Long) ReflectionUtils.getField(ReflectionUtils.findField(pageClass, GroovyPageParser.CONSTANT_NAME_LAST_MODIFIED), null);
@@ -133,8 +144,7 @@ public GroovyPageMetaInfo(Class<?> pageClass) {
 
         try {
             readHtmlData();
-        }
-        catch (IOException e) {
+        } catch (IOException e) {
             throw new RuntimeException("Problem reading html data for page class " + pageClass, e);
         }
     }
@@ -217,8 +227,7 @@ private void readHtmlData() throws IOException {
                     htmlParts[i] = input.readUTF();
                 }
             }
-        }
-        finally {
+        } finally {
             IOUtils.closeQuietly(input);
         }
     }
@@ -239,8 +248,7 @@ private void readLineNumbers() throws IOException {
             for (int i = 0; i < arrayLen; i++) {
                 lineNumbers[i] = input.readInt();
             }
-        }
-        finally {
+        } finally {
             IOUtils.closeQuietly(input);
         }
     }
@@ -282,8 +290,28 @@ public Class<?> getPageClass() {
         return pageClass;
     }
 
+    public GroovyPage getPageClassInstance() throws InstantiationException, IllegalAccessException, NoSuchMethodException, InvocationTargetException {
+        SoftReference<GroovyPage> pageSoftRef = pageInstance.get();
+        GroovyPage pageCacheEntry = pageSoftRef != null ? pageSoftRef.get() : null;
+        if (pageCacheEntry == null) {
+            pageCacheEntry = (GroovyPage) pageClassConstructor.newInstance();
+            pageCacheEntry.initCommonRun(this);
+            if (!isModelFieldsMode()) {
+                pageInstance.set(new SoftReference<>(pageCacheEntry));
+            }
+        }
+        return pageCacheEntry;
+    }
+
     public void setPageClass(Class<?> pageClass) {
         this.pageClass = pageClass;
+
+        try {
+            this.pageClassConstructor = pageClass.getConstructor();
+        } catch (NoSuchMethodException e) {
+            throw new RuntimeException(e);
+        }
+        pageInstance.set(null);
         initializePluginPath();
     }
 
@@ -323,8 +351,7 @@ private synchronized int[] getPrecompiledLineNumbers() {
         if (lineNumbers == null) {
             try {
                 readLineNumbers();
-            }
-            catch (IOException e) {
+            } catch (IOException e) {
                 LOG.warn("Problem reading precompiled linenumbers", e);
             }
         }
@@ -359,6 +386,18 @@ public String[] getHtmlParts() {
 
     public void setHtmlParts(String[] htmlParts) {
         this.htmlParts = htmlParts;
+        this.htmlPartsSet = new HashSet<>();
+        if (htmlParts != null) {
+            for (String htmlPart : htmlParts) {
+                if (htmlPart != null) {
+                    htmlPartsSet.add(System.identityHashCode(htmlPart));
+                }
+            }
+        }
+    }
+
+    Set<Integer> getHtmlPartsSet() {
+        return this.htmlPartsSet;
     }
 
     public void applyLastModifiedFromResource(Resource resource) {
@@ -394,22 +433,18 @@ private long establishLastModified(Resource resource) {
             urlc.setDoInput(false);
             urlc.setDoOutput(false);
             last = urlc.getLastModified();
-        }
-        catch (FileNotFoundException fnfe) {
+        } catch (FileNotFoundException fnfe) {
             last = -1;
-        }
-        catch (IOException e) {
+        } catch (IOException e) {
             last = -1;
-        }
-        finally {
+        } finally {
             if (urlc != null) {
                 try {
                     InputStream is = urlc.getInputStream();
                     if (is != null) {
                         is.close();
                     }
-                }
-                catch (IOException e) {
+                } catch (IOException e) {
                     // ignore
                 }
             }

grails-gsp/core/src/main/groovy/org/grails/gsp/GroovyPageWritable.java

@@ -30,8 +30,8 @@
 import groovy.lang.Binding;
 import groovy.lang.Writable;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import grails.util.Environment;
 import org.grails.taglib.AbstractTemplateVariableBinding;
@@ -47,7 +47,7 @@
  * @since 0.5
  */
 public class GroovyPageWritable implements Writable {
-    private static final Log LOG = LogFactory.getLog(GroovyPageWritable.class);
+    private static final Logger LOG = LoggerFactory.getLogger(GroovyPageWritable.class);
     private static final String GSP_NONE_CODEC_NAME = "none";
     private GroovyPageMetaInfo metaInfo;
     private OutputContextLookup outputContextLookup;
@@ -101,8 +101,7 @@ protected Writer doWriteTo(OutputContext outputContext, Writer out) throws IOExc
             // Set it to TEXT
             outputContext.setContentType(GROOVY_SOURCE_CONTENT_TYPE); // must come before response.getOutputStream()
             writeGroovySourceToResponse(metaInfo, out);
-        }
-        else {
+        } else {
             // Set it to HTML by default
             if (metaInfo.getCompilationException() != null) {
                 throw metaInfo.getCompilationException();
@@ -125,9 +124,7 @@ protected Writer doWriteTo(OutputContext outputContext, Writer out) throws IOExc
                 // only try to set content type when evaluating top level GSP
                 boolean contentTypeAlreadySet = outputContext.isContentTypeAlreadySet();
                 if (!contentTypeAlreadySet) {
-                    if (LOG.isDebugEnabled()) {
-                        LOG.debug("Writing output with content type: " + metaInfo.getContentType());
-                    }
+                    LOG.debug("Writing output with content type: {}", metaInfo.getContentType());
                     outputContext.setContentType(metaInfo.getContentType()); // must come before response.getWriter()
                 }
             }
@@ -136,22 +133,26 @@ protected Writer doWriteTo(OutputContext outputContext, Writer out) throws IOExc
             if (hasRequest) {
                 outputContext.setBinding(binding);
             }
-
+            Binding existingBinding = null;
             GroovyPage page = null;
             try {
-                page = (GroovyPage) metaInfo.getPageClass().newInstance();
+                page = metaInfo.getPageClassInstance();
+                existingBinding = page.getBinding();
             } catch (Exception e) {
                 throw new GroovyPagesException("Problem instantiating page class", e);
             }
+
             page.setBinding(binding);
             binding.setOwner(page);
 
             page.initRun(out, outputContext, metaInfo);
 
             try {
                 page.run();
-            }
-            finally {
+            } finally {
+                if (existingBinding != null) {
+                    page.setBinding(existingBinding);
+                }
                 page.cleanup();
                 if (hasRequest) {
                     if (newParentCreated) {
@@ -220,13 +221,12 @@ protected void writeInputStreamToResponse(InputStream in, Writer out) throws IOE
             Reader reader = new InputStreamReader(in, "UTF-8");
             char[] buf = new char[8192];
 
-            for (;;) {
+            for (; ; ) {
                 int read = reader.read(buf);
                 if (read <= 0) break;
                 out.write(buf, 0, read);
             }
-        }
-        finally {
+        } finally {
             out.close();
             in.close();
         }
@@ -249,8 +249,7 @@ protected void writeGroovySourceToResponse(GroovyPageMetaInfo info, Writer out)
         try {
             try {
                 in.reset();
-            }
-            catch (IOException e) {
+            } catch (IOException e) {
                 // ignore
             }
             BufferedReader reader = new BufferedReader(new InputStreamReader(in, "UTF-8"));
@@ -288,8 +287,7 @@ protected void writeGroovySourceToResponse(GroovyPageMetaInfo info, Writer out)
                 out.write(line);
                 out.write('\n');
             }
-        }
-        finally {
+        } finally {
             out.close();
             in.close();
         }

grails-gsp/core/src/main/groovy/org/grails/gsp/GroovyPagesTemplateEngine.java

@@ -418,6 +418,27 @@ public Template createTemplate(String txt, String pageName) throws IOException {
         return createTemplate(new ByteArrayResource(txt.getBytes(StandardCharsets.UTF_8), pageName), pageName, pageName != null);
     }
 
+    /**
+     * Creates a Template using the given text for the Template and the given name. The name
+     * of the template is required
+     *
+     * @param txt The URI of the page to create the template for
+     * @param pageName The name of the page being parsed
+     * @param cache If the template should be cached
+     *
+     * @return The Template instance
+     * @throws CompilationFailedException
+     * @throws IOException Thrown if an IO exception occurs creating the Template
+     */
+    public Template createTemplate(String txt, String pageName, boolean cache) throws IOException {
+        Assert.hasLength(txt, "Argument [txt] cannot be null or blank");
+        Assert.hasLength(pageName, "Argument [pageName] cannot be null or blank");
+
+        return createTemplate(new ByteArrayResource(txt.getBytes(StandardCharsets.UTF_8), pageName), pageName, cache);
+    }
+
+    /**
+     * Creates a Template using the given text for the Template and the given name. The name
     /**
      * Creates a Template for the given file
      *