Share project "druid" into "http://code.alibabatech.com/svn/druid"

git-svn-id: http://code.alibabatech.com/svn/druid/trunk@2 b9813039-fb51-4c41-a8b9-e21c2acb5095

src/main/java/com/alibaba/druid/sql/ast/SQLObjectImpl.java

@@ -0,0 +1,92 @@
+package com.alibaba.druid.sql.ast;
+
+import java.io.Serializable;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+
+public abstract class SQLObjectImpl implements SQLObject, Serializable {
+    private static final long serialVersionUID = 5569722716326763762L;
+
+    private SQLObject parent;
+
+    private Map<String, Object> attributes;
+
+    public SQLObjectImpl() {
+    }
+
+    public final void accept(SQLASTVisitor visitor) {
+        if (visitor == null) {
+            throw new IllegalArgumentException();
+        }
+
+        visitor.preVisit(this);
+
+        accept0(visitor);
+
+        visitor.postVisit(this);
+    }
+
+    protected abstract void accept0(SQLASTVisitor visitor);
+
+    protected final void acceptChild(SQLASTVisitor visitor, List<? extends SQLObject> children) {
+        for (SQLObject child : children)
+            acceptChild(visitor, child);
+    }
+
+    protected final void acceptChild(SQLASTVisitor visitor, SQLObject child) {
+        if (child == null) {
+            return;
+        }
+
+        child.accept(visitor);
+    }
+
+    public void output(StringBuffer buf) {
+        buf.append(super.toString());
+    }
+
+    public String toString() {
+        StringBuffer buf = new StringBuffer();
+        output(buf);
+        return buf.toString();
+    }
+
+    public SQLObject getParent() {
+        return parent;
+    }
+
+    public void setParent(SQLObject parent) {
+        this.parent = parent;
+    }
+
+    public Map<String, Object> getAttributes() {
+        if (attributes == null) {
+            attributes = new HashMap<String, Object>(1);
+        }
+
+        return attributes;
+    }
+
+    public Object getAttribute(String name) {
+        if (attributes == null) {
+            return null;
+        }
+
+        return attributes.get(name);
+    }
+
+    public void putAttribute(String name, Object value) {
+        if (attributes == null) {
+            attributes = new HashMap<String, Object>(1);
+        }
+
+        attributes.put(name, value);
+    }
+
+    public Map<String, Object> getAttributesDirect() {
+        return attributes;
+    }
+}