From 6d5f1bdc6b4f390a347af99ead32a1a0729e8041 Mon Sep 17 00:00:00 2001 From: Stefan Bodewig Date: Sat, 20 Mar 2021 19:00:36 +0100 Subject: [PATCH] add discardOutput and discardError to redirector, apply, exec, java --- WHATSNEW | 5 ++ manual/Tasks/apply.html | 21 ++++++ manual/Tasks/exec.html | 21 ++++++ manual/Tasks/java.html | 21 ++++++ manual/Types/redirector.html | 21 ++++++ .../apache/tools/ant/taskdefs/ExecTask.java | 30 +++++++++ .../org/apache/tools/ant/taskdefs/Java.java | 30 +++++++++ .../apache/tools/ant/taskdefs/Redirector.java | 64 ++++++++++++++++++- .../tools/ant/util/NullOutputStream.java | 53 +++++++++++++++ src/tests/antunit/taskdefs/exec/exec-test.xml | 27 ++++++++ 10 files changed, 291 insertions(+), 2 deletions(-) create mode 100644 src/main/org/apache/tools/ant/util/NullOutputStream.java diff --git a/WHATSNEW b/WHATSNEW index 9d3f7c0f1..2036b94a2 100644 --- a/WHATSNEW +++ b/WHATSNEW @@ -69,6 +69,11 @@ Other changes: task. Bugzilla Report 65089 + * added new disardOutput and discardError properties to redirector + and the exec, apply and java tasks which can be used to completely + discard any (error) output. This is a platform independent + alternative to directiong output to any kind of null device. + Changes from Ant 1.10.8 TO Ant 1.10.9 ===================================== diff --git a/manual/Tasks/apply.html b/manual/Tasks/apply.html index b77cd7671..fad38c073 100644 --- a/manual/Tasks/apply.html +++ b/manual/Tasks/apply.html @@ -258,6 +258,27 @@ standard input.

Whether to bypass timestamp comparisons for target files. Since Ant 1.6.3. No; default is false + + discardOutput + Whether output should completely be discarded. This setting is + incompatible with any setting that redirects output to files or + properties.
+ If you set this to true error output will be discared as + well unless you redirect error output to files, properties or + enable logError. + Since Ant 1.10.10 + + No; defaults to false + + + discardError + Whether error output should completely be discarded. This + setting is incompatible with any setting that redirects error + output to files or properties as well as logError. + Since Ant 1.10.10 + + No; defaults to false +

Parameters specified as nested elements

fileset

diff --git a/manual/Tasks/exec.html b/manual/Tasks/exec.html index b298a65ec..05eb9a5b1 100644 --- a/manual/Tasks/exec.html +++ b/manual/Tasks/exec.html @@ -262,6 +262,27 @@ standard input.

when resolving the location of the executable. since Ant 1.6.3 No; default is false + + discardOutput + Whether output should completely be discarded. This setting is + incompatible with any setting that redirects output to files or + properties.
+ If you set this to true error output will be discared as + well unless you redirect error output to files, properties or + enable logError. + Since Ant 1.10.10 + + No; defaults to false + + + discardError + Whether error output should completely be discarded. This + setting is incompatible with any setting that redirects error + output to files or properties as well as logError. + Since Ant 1.10.10 + + No; defaults to false +

Examples

diff --git a/manual/Tasks/java.html b/manual/Tasks/java.html
index 98c4bd36b..31f4f0143 100644
--- a/manual/Tasks/java.html
+++ b/manual/Tasks/java.html
@@ -218,6 +218,27 @@ because it tries to read from the standard input.

       forked JVM will be the same as those of the JVM running Ant. since Ant 1.7
     No; default is false, ignored if fork is false
   
+  
+    discardOutput
+    Whether output should completely be discarded. This setting is
+      incompatible with any setting that redirects output to files or
+      properties.

+      If you set this to true error output will be discared as
+      well unless you redirect error output to files, properties or
+      enable logError.
+      Since Ant 1.10.10
+    
+    No; defaults to false
+  
+  
+    discardError
+    Whether error output should completely be discarded. This
+      setting is incompatible with any setting that redirects error
+      output to files or properties as well as logError.
+      Since Ant 1.10.10
+    
+    No; defaults to false
+  
 
 
Parameters specified as nested elements

 
arg and jvmarg

diff --git a/manual/Types/redirector.html b/manual/Types/redirector.html
index c0a1c0eed..94ecd4852 100644
--- a/manual/Types/redirector.html
+++ b/manual/Types/redirector.html
@@ -129,6 +129,27 @@ specify source (input) and destination (output/error) files.

     
     No; default is false
   
+  
+    discardOutput
+    Whether output should completely be discarded. This setting is
+      incompatible with any setting that redirects output to files or
+      properties.

+      If you set this to true error output will be discared as
+      well unless you redirect error output to files, properties or
+      enable logError.
+      Since Ant 1.10.10
+    
+    No; defaults to false
+  
+  
+    discardError
+    Whether error output should completely be discarded. This
+      setting is incompatible with any setting that redirects error
+      output to files or properties as well as logError.
+      Since Ant 1.10.10
+    
+    No; defaults to false
+  
 
 
Parameters specified as nested elements

 
inputmapper

diff --git a/src/main/org/apache/tools/ant/taskdefs/ExecTask.java b/src/main/org/apache/tools/ant/taskdefs/ExecTask.java
index e92536974..eebf6ae12 100644
--- a/src/main/org/apache/tools/ant/taskdefs/ExecTask.java
+++ b/src/main/org/apache/tools/ant/taskdefs/ExecTask.java
@@ -380,6 +380,36 @@ public class ExecTask extends Task {
         incompatibleWithSpawn |= append;
     }
 
+    /**
+     * Whether output should be discarded.
+     *
+     * 
Defaults to false.

+     *
+     * @param discard
+     *            if true output streams are discarded.
+     *
+     * @since Ant 1.10.10
+     * @see #setDiscardError
+     */
+    public void setDiscardOutput(final boolean discard) {
+        redirector.setDiscardOutput(discard);
+    }
+
+    /**
+     * Whether error output should be discarded.
+     *
+     * 
Defaults to false.

+     *
+     * @param discard
+     *            if true error streams are discarded.
+     *
+     * @since Ant 1.10.10
+     * @see #setDiscardOutput
+     */
+    public void setDiscardError(final boolean discard) {
+        redirector.setDiscardError(discard);
+    }
+
     /**
      * Add a RedirectorElement to this task.
      *
diff --git a/src/main/org/apache/tools/ant/taskdefs/Java.java b/src/main/org/apache/tools/ant/taskdefs/Java.java
index 7acdad4e0..7c55bbe6e 100644
--- a/src/main/org/apache/tools/ant/taskdefs/Java.java
+++ b/src/main/org/apache/tools/ant/taskdefs/Java.java
@@ -707,6 +707,36 @@ public class Java extends Task {
         incompatibleWithSpawn |= append;
     }
 
+    /**
+     * Whether output should be discarded.
+     *
+     * 
Defaults to false.

+     *
+     * @param discard
+     *            if true output streams are discarded.
+     *
+     * @since Ant 1.10.10
+     * @see #setDiscardError
+     */
+    public void setDiscardOutput(final boolean discard) {
+        redirector.setDiscardOutput(discard);
+    }
+
+    /**
+     * Whether error output should be discarded.
+     *
+     * 
Defaults to false.

+     *
+     * @param discard
+     *            if true error streams are discarded.
+     *
+     * @since Ant 1.10.10
+     * @see #setDiscardOutput
+     */
+    public void setDiscardError(final boolean discard) {
+        redirector.setDiscardError(discard);
+    }
+
     /**
      * Set the timeout in milliseconds after which the process will be killed.
      *
diff --git a/src/main/org/apache/tools/ant/taskdefs/Redirector.java b/src/main/org/apache/tools/ant/taskdefs/Redirector.java
index ee91adbd1..9950e9a05 100644
--- a/src/main/org/apache/tools/ant/taskdefs/Redirector.java
+++ b/src/main/org/apache/tools/ant/taskdefs/Redirector.java
@@ -45,6 +45,7 @@ import org.apache.tools.ant.util.KeepAliveOutputStream;
 import org.apache.tools.ant.util.LazyFileOutputStream;
 import org.apache.tools.ant.util.LeadPipeInputStream;
 import org.apache.tools.ant.util.LineOrientedOutputStreamRedirector;
+import org.apache.tools.ant.util.NullOutputStream;
 import org.apache.tools.ant.util.OutputStreamFunneler;
 import org.apache.tools.ant.util.ReaderInputStream;
 import org.apache.tools.ant.util.TeeOutputStream;
@@ -197,6 +198,11 @@ public class Redirector {
     /** Is the output binary or can we safely split it into lines? */
     private boolean outputIsBinary = false;
 
+    /** Flag which indicates if error and output files are to be discarded. */
+    private boolean discardOut = false;
+
+    private boolean discardErr = false;
+
     /**
      * Create a redirector instance for the given task
      *
@@ -442,6 +448,40 @@ public class Redirector {
         }
     }
 
+    /**
+     * Whether output should be discarded.
+     *
+     * 
Defaults to false.

+     *
+     * @param discard
+     *            if true output streams are discarded.
+     *
+     * @since Ant 1.10.10
+     * @see #setDiscardError
+     */
+    public void setDiscardOutput(final boolean discard) {
+        synchronized (outMutex) {
+            discardOut = discard;
+        }
+    }
+
+    /**
+     * Whether error output should be discarded.
+     *
+     * 
Defaults to false.

+     *
+     * @param discard
+     *            if true error streams are discarded.
+     *
+     * @since Ant 1.10.10
+     * @see #setDiscardOutput
+     */
+    public void setDiscardError(final boolean discard) {
+        synchronized (errMutex) {
+            discardErr = discard;
+        }
+    }
+
     /**
      * If true, (error and non-error) output will be "teed", redirected as
      * specified while being sent to Ant's logging mechanism as if no
@@ -694,7 +734,17 @@ public class Redirector {
 
     /** outStreams */
     private void outStreams() {
-        if (out != null && out.length > 0) {
+        final boolean haveOutputFiles = out != null && out.length > 0;
+        if (discardOut) {
+            if (haveOutputFiles || outputProperty != null) {
+                throw new BuildException("Cant discard output when output or outputProperty"
+                        + " are set");
+            }
+            managingTask.log("Discarding output", Project.MSG_VERBOSE);
+            outputStream = NullOutputStream.INSTANCE;
+            return;
+        }
+        if (haveOutputFiles) {
             final String logHead = "Output "
                     + ((appendOut) ? "appended" : "redirected") + " to ";
             outputStream = foldFiles(out, logHead, Project.MSG_VERBOSE,
@@ -716,7 +766,17 @@ public class Redirector {
     }
 
     private void errorStreams() {
-        if (error != null && error.length > 0) {
+        final boolean haveErrorFiles = error != null && error.length > 0;
+        if (discardErr) {
+            if (haveErrorFiles || errorProperty != null || logError) {
+                throw new BuildException("Cant discard error output when error, errorProperty"
+                        + " or logError are set");
+            }
+            managingTask.log("Discarding error output", Project.MSG_VERBOSE);
+            errorStream = NullOutputStream.INSTANCE;
+            return;
+        }
+        if (haveErrorFiles) {
             final String logHead = "Error "
                     + ((appendErr) ? "appended" : "redirected") + " to ";
             errorStream = foldFiles(error, logHead, Project.MSG_VERBOSE,
diff --git a/src/main/org/apache/tools/ant/util/NullOutputStream.java b/src/main/org/apache/tools/ant/util/NullOutputStream.java
new file mode 100644
index 000000000..689ac495c
--- /dev/null
+++ b/src/main/org/apache/tools/ant/util/NullOutputStream.java
@@ -0,0 +1,53 @@
+/*
+ *  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
+ *
+ *      https://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 org.apache.tools.ant.util;
+
+import java.io.OutputStream;
+
+/**
+ * OutputStream that completely discards all data written to it.
+ *
+ * @since Ant 1.10.10
+ */
+public class NullOutputStream extends OutputStream {
+
+    /**
+     * Shared instance which is safe to use concurrently as the stream
+     * doesn't hold any state at all.
+     */
+    public static NullOutputStream INSTANCE = new NullOutputStream();
+
+    /**
+     * Doesn't do anything.
+     */
+    @Override
+    public void write(byte[] b) { }
+
+    /**
+     * Doesn't do anything.
+     */
+    @Override
+    public void write(byte[] b, int off, int len) { }
+
+    /**
+     * Doesn't do anything.
+     */
+    @Override
+    public void write(int i) { }
+}
diff --git a/src/tests/antunit/taskdefs/exec/exec-test.xml b/src/tests/antunit/taskdefs/exec/exec-test.xml
index c91db9bd7..bbe95e510 100644
--- a/src/tests/antunit/taskdefs/exec/exec-test.xml
+++ b/src/tests/antunit/taskdefs/exec/exec-test.xml
@@ -707,4 +707,31 @@ public class Hello {
         
     
 
+    
+        
+            
+            
+        
+        
+        
+    
+
+    
+        
+            
+            
+        
+        
+        
+    
+
+    
+        
+            
+            
+        
+        
+        
+    
+