Fix Craft Entity constructors and toStrings.

Also, standardise getHandle and clean up in general.
getHandle is now using the 'entity' member variable instead of
super.getHandle, as this reduces the number of chained calls needed.

src/main/java/net/minecraft/server/EntityPotion.java

@@ -0,0 +1,87 @@
+package net.minecraft.server;
+
+import java.util.Iterator;
+import java.util.List;
+
+public class EntityPotion extends EntityProjectile {
+
+    private int d;
+
+    public EntityPotion(World world) {
+        super(world);
+    }
+
+    public EntityPotion(World world, EntityLiving entityliving, int i) {
+        super(world, entityliving);
+        this.d = i;
+    }
+
+    public EntityPotion(World world, double d0, double d1, double d2, int i) {
+        super(world, d0, d1, d2);
+        this.d = i;
+    }
+
+    protected float e() {
+        return 0.05F;
+    }
+
+    protected float c() {
+        return 0.5F;
+    }
+
+    protected float d() {
+        return -20.0F;
+    }
+
+    public int f() {
+        return this.d;
+    }
+
+    protected void a(MovingObjectPosition movingobjectposition) {
+        if (!this.world.isStatic) {
+            List list = Item.POTION.b(this.d);
+
+            if (list != null && !list.isEmpty()) {
+                AxisAlignedBB axisalignedbb = this.boundingBox.b(4.0D, 2.0D, 4.0D);
+                List list1 = this.world.a(EntityLiving.class, axisalignedbb);
+
+                if (list1 != null && !list1.isEmpty()) {
+                    Iterator iterator = list1.iterator();
+
+                    while (iterator.hasNext()) {
+                        Entity entity = (Entity) iterator.next();
+                        double d0 = this.i(entity);
+
+                        if (d0 < 16.0D) {
+                            double d1 = 1.0D - Math.sqrt(d0) / 4.0D;
+
+                            if (entity == movingobjectposition.entity) {
+                                d1 = 1.0D;
+                            }
+
+                            Iterator iterator1 = list.iterator();
+
+                            while (iterator1.hasNext()) {
+                                MobEffect mobeffect = (MobEffect) iterator1.next();
+                                int i = mobeffect.getEffectId();
+
+                                if (MobEffectList.byId[i].b()) {
+                                    MobEffectList.byId[i].a(this.shooter, (EntityLiving) entity, mobeffect.getAmplifier(), d1);
+                                } else {
+                                    int j = (int) (d1 * (double) mobeffect.getDuration() + 0.5D);
+
+                                    if (j > 20) {
+                                        ((EntityLiving) entity).addEffect(new MobEffect(i, j, mobeffect.getAmplifier()));
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+
+            this.world.f(2002, (int) Math.round(this.locX), (int) Math.round(this.locY), (int) Math.round(this.locZ), this.d);
+            this.die();
+        }
+    }
+}