OJ (aka OpenJava) modernization/mirroring

Signed-off-by: Kenny Ballou <kballou@devnulllabs.io>

1 files changed, 138 insertions, 0 deletions

diff --git a/src/main/java/io/devnulllabs/openjava/tools/WriterStack.java b/src/main/java/io/devnulllabs/openjava/tools/WriterStack.java
new file mode 100644
index 0000000..a3d86d7
--- /dev/null
+++ b/src/main/java/io/devnulllabs/openjava/tools/WriterStack.java
@@ -0,0 +1,138 @@
+/***
+ *  WriterStack.java 1.0
+ * this is a stack for Writer.
+ * wrapper class of java.util.Stack
+ *  
+ * @see java.io.Writer
+ * @see java.util.Stack
+ * @version last updated: 06/11/97
+ * @author  Michiaki Tatsubori
+ ***/
+/* package */
+package io.devnulllabs.openjava.tools;
+
+
+/* import */
+import java.io.BufferedWriter;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.PrintWriter;
+import java.io.Writer;
+import java.util.EmptyStackException;
+import java.util.Stack;
+
+
+/**
+ * Wrapper class of class Stack to specialize into Writer.
+ **/
+public class WriterStack
+{
+  private Stack stack = null;
+  private static PrintWriter defaultWriter
+      = new PrintWriter(
+            new BufferedWriter(
+              new OutputStreamWriter( System.out ) ) );
+
+  /**
+   * Constructs this stack with an element(standard output).
+   **/
+  public WriterStack() {
+    stack = new Stack();
+    stack.push( defaultWriter );
+  }
+
+  /**
+   * Constructs this stack with the specified print writer.
+   **/
+  public WriterStack( PrintWriter writer ) {
+    stack = new Stack();
+    stack.push( writer );
+  }
+
+  /**
+   * Constructs this stack with the specified writer.
+   **/
+  public WriterStack( Writer writer ) {
+    stack = new Stack();
+    stack.push( new PrintWriter( writer ) );
+  }
+
+  /**
+   * Constructs this stack with the specified output stream.
+   **/
+  public WriterStack( OutputStream out ) {
+    stack = new Stack();
+    stack.push( new PrintWriter( new OutputStreamWriter( out ) ) );
+  }
+
+  /**
+   * Looks at the print writer at the top of this stack 
+   * without removing it from the stack. 
+   *
+   * @return the print writer at the top of this stack. 
+   **/
+  public PrintWriter peek() {
+    try{
+      return (PrintWriter)stack.peek();
+    }catch( EmptyStackException ex ){
+      System.err.println( ex );
+      return defaultWriter;
+    }
+  }
+
+  /**
+   * Removes the print writer at the top of this stack and
+   * returns that print writer as the value of this function. 
+   * 
+   * @return The object at the top of this stack. 
+   **/
+  public PrintWriter pop() {
+    try{
+      return (PrintWriter)stack.pop();
+    }catch( EmptyStackException ex ){
+      System.err.println( ex );
+      return defaultWriter;
+    }
+  }
+
+  /**
+   * Pushes a print writer onto the top of this stack. 
+   *
+   * @param writer the print writer to be pushed onto this stack. 
+   * @return the item argument. 
+   **/
+  public void push( PrintWriter writer ) {
+    stack.push( writer );
+  }
+
+  /**
+   * Pushes a print writer onto the top of this stack. 
+   *
+   * @param writer the writer to be pushed onto this stack. 
+   * @return the item argument. 
+   **/
+  public void push( Writer writer ) {
+    stack.push( new PrintWriter( writer ) );
+  }
+
+  /**
+   * Pushes a print writer from the specified print stream
+   * onto the top of this stack. 
+   *
+   * @param ostream the output stream to be pushed onto this stack. 
+   * @return the item argument. 
+   **/
+  public void push( OutputStream ostream ) {
+    stack.push( new PrintWriter( new OutputStreamWriter( ostream ) ) );
+  }
+
+  /**
+   * Tests if this stack is empty. 
+   *
+   * @return true if this stack is empty; false otherwise. 
+   **/
+  public boolean empty() {
+    return stack.empty();
+  }
+
+}